- Replace 'if(' with 'if ('.
[fw/openocd] / src / xsvf / xsvf.c
index 09736af6d185933ce1b2eaa0cd5b734108b80868..6356843989307739932b45fd4fb571a80c17e457 100644 (file)
 /***************************************************************************
- *   Copyright (C) 2005 by Dominic Rath                                    *
- *   Dominic.Rath@gmx.de                                                   *
- *                                                                         *
- *   This program is free software; you can redistribute it and/or modify  *
- *   it under the terms of the GNU General Public License as published by  *
- *   the Free Software Foundation; either version 2 of the License, or     *
- *   (at your option) any later version.                                   *
- *                                                                         *
- *   This program is distributed in the hope that it will be useful,       *
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
- *   GNU General Public License for more details.                          *
- *                                                                         *
- *   You should have received a copy of the GNU General Public License     *
- *   along with this program; if not, write to the                         *
- *   Free Software Foundation, Inc.,                                       *
- *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
+ *      Copyright (C) 2005 by Dominic Rath                                                                        *
+ *      Dominic.Rath@gmx.de                                                                                                       *
+ *                                                                                                                                                *
+ *      Copyright (C) 2007,2008 Ã˜yvind Harboe                                                             *
+ *      oyvind.harboe@zylin.com                                                                                                   *
+ *                                                                                                                                                *
+ *      Copyright (C) 2008 Peter Hettkamp                                                                         *
+ *      peter.hettkamp@htp-tel.de                                                                                         *
+ *                                                                                                                                                *
+ *      Copyright (C) 2009 SoftPLC Corporation. http://softplc.com             *
+ *      Dick Hollenbeck <dick@softplc.com>                                                                        *
+ *                                                                          *
+ *      This program is free software; you can redistribute it and/or modify   *
+ *      it under the terms of the GNU General Public License as published by   *
+ *      the Free Software Foundation; either version 2 of the License, or         *
+ *      (at your option) any later version.                                                                       *
+ *                                                                                                                                                *
+ *      This program is distributed in the hope that it will be useful,                   *
+ *      but WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the             *
+ *      GNU General Public License for more details.                                              *
+ *                                                                                                                                                *
+ *      You should have received a copy of the GNU General Public License         *
+ *      along with this program; if not, write to the                                             *
+ *      Free Software Foundation, Inc.,                                                                                   *
+ *      59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.                         *
  ***************************************************************************/
+
+
+/* The specification for SVF is available here:
+ * http://www.asset-intertech.com/support/svf.pdf
+ * Below, this document is refered to as the "SVF spec".
+ *
+ * The specification for XSVF is available here:
+ * http://www.xilinx.com/support/documentation/application_notes/xapp503.pdf
+ * Below, this document is refered to as the "XSVF spec".
+ */
+
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
 #include "xsvf.h"
-
 #include "jtag.h"
-#include "command.h"
-#include "log.h"
 
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <string.h>
 
-#include <sys/time.h>
-#include <time.h>
+/* XSVF commands, from appendix B of xapp503.pdf  */
+#define XCOMPLETE              0x00
+#define XTDOMASK                       0x01
+#define XSIR                           0x02
+#define XSDR                           0x03
+#define XRUNTEST                       0x04
+#define XREPEAT                        0x07
+#define XSDRSIZE                       0x08
+#define XSDRTDO                        0x09
+#define XSETSDRMASKS           0x0A
+#define XSDRINC                        0x0B
+#define XSDRB                  0x0C
+#define XSDRC                  0x0D
+#define XSDRE                  0x0E
+#define XSDRTDOB                       0x0F
+#define XSDRTDOC                       0x10
+#define XSDRTDOE                       0x11
+#define XSTATE                 0x12
+#define XENDIR                 0x13
+#define XENDDR                 0x14
+#define XSIR2                  0x15
+#define XCOMMENT                       0x16
+#define XWAIT                  0x17
 
-#define XSTATE_MAX_PATH (12)
+/* XWAITSTATE is not in the xilinx XSVF spec, but the svf2xsvf.py translator
+ * generates this.  Arguably it is needed because the XSVF XRUNTEST command
+ * was ill conceived and does not directly flow out of the SVF RUNTEST command.
+ * This XWAITSTATE does map directly from the SVF RUNTEST command.
+ */
+#define XWAITSTATE             0x18
 
-int handle_xsvf_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+/* Lattice has extended the SVF file format, and Dick Hollenbeck's python based
+ * SVF2XSVF converter supports these 3 additional XSVF opcodes, LCOUNT, LDELAY, LSDR.
+ * Here is an example of usage of the 3 lattice opcode extensions:
 
-int xsvf_fd = 0;
+! Set the maximum loop count to 25.
+LCOUNT 25;
+! Step to DRPAUSE give 5 clocks and wait for 1.00e+000 SEC.
+LDELAY DRPAUSE 5 TCK   1.00E-003 SEC;
+! Test for the completed status. Match means pass.
+! Loop back to LDELAY line if not match and loop count less than 25.
 
-u8 *dr_out_buf;        /* from host to device (TDI) */
-u8 *dr_in_buf; /* from device to host (TDO) */
-u8 *dr_in_mask;
+LSDR 1  TDI  (0)
+               TDO  (1);
+*/
 
-int xsdrsize = 0;
-int xruntest = 0;      /* number of TCK cycles / microseconds */
-int xrepeat = 0x20; /* number of XC9500 retries */
+#define LCOUNT                 0x19
+#define LDELAY                 0x1A
+#define LSDR                           0x1B
+#define XTRST                  0x1C
 
-int xendir = 0;
-int xenddr = 0;
 
-enum tap_state xsvf_to_tap[] =
-{
-       TAP_TLR, TAP_RTI,
-       TAP_SDS, TAP_CD, TAP_SD, TAP_E1D, TAP_PD, TAP_E2D, TAP_UD,
-       TAP_SIS, TAP_CI, TAP_SI, TAP_E1I, TAP_PI, TAP_E2I, TAP_UI,
-};
+/* XSVF valid state values for the XSTATE command, from appendix B of xapp503.pdf */
+#define XSV_RESET              0x00
+#define XSV_IDLE                       0x01
+#define XSV_DRSELECT           0x02
+#define XSV_DRCAPTURE  0x03
+#define XSV_DRSHIFT            0x04
+#define XSV_DREXIT1            0x05
+#define XSV_DRPAUSE            0x06
+#define XSV_DREXIT2            0x07
+#define XSV_DRUPDATE           0x08
+#define XSV_IRSELECT           0x09
+#define XSV_IRCAPTURE  0x0A
+#define XSV_IRSHIFT            0x0B
+#define XSV_IREXIT1            0x0C
+#define XSV_IRPAUSE            0x0D
+#define XSV_IREXIT2            0x0E
+#define XSV_IRUPDATE           0x0F
 
-int tap_to_xsvf[] =
-{
-       0x0, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x1, 0x9, 0xa, 0xb, 0xc, 0xe, 0xf
-};
+/* arguments to XTRST */
+#define XTRST_ON                       0
+#define XTRST_OFF              1
+#define XTRST_Z                        2
+#define XTRST_ABSENT           3
 
+#define XSTATE_MAX_PATH 12
 
-/* xsvf has it's own definition of a statemove. This needs
- * to be handled according to the specs, which has nothing
- * to do with the JTAG spec or OpenOCD as such.
- * 
- * Implemented via jtag_add_pathmove().
- */
-void xsvf_add_statemove(enum tap_state state)
+static int handle_xsvf_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
+
+static int xsvf_fd = 0;
+
+
+/* map xsvf tap state to an openocd "tap_state_t" */
+static tap_state_t xsvf_to_tap( int xsvf_state )
 {
-       enum tap_state moves[7]; /* max # of transitions */
-       int i; 
-       enum tap_state curstate=cmd_queue_cur_state;
-       u8 move=tap_move[cmd_queue_cur_state][state];
-       
-       if ((state!=TAP_TLR)&&(state==cmd_queue_cur_state))
-               return;
-       for (i=0; i<7; i++)
+       tap_state_t     ret;
+
+       switch( xsvf_state )
        {
-               int j=(move>>i)&1;
-               if (j)
-               {
-                       curstate=tap_transitions[curstate].high;
-               } else
-               {
-                       curstate=tap_transitions[curstate].low;
-               }
-               moves[i]=curstate;
+       case XSV_RESET:                 ret = TAP_RESET;                        break;
+       case XSV_IDLE:                  ret = TAP_IDLE;                 break;
+       case XSV_DRSELECT:              ret = TAP_DRSELECT;             break;
+       case XSV_DRCAPTURE:             ret = TAP_DRCAPTURE;            break;
+       case XSV_DRSHIFT:               ret = TAP_DRSHIFT;              break;
+       case XSV_DREXIT1:               ret = TAP_DREXIT1;              break;
+       case XSV_DRPAUSE:               ret = TAP_DRPAUSE;              break;
+       case XSV_DREXIT2:               ret = TAP_DREXIT2;              break;
+       case XSV_DRUPDATE:              ret = TAP_DRUPDATE;             break;
+       case XSV_IRSELECT:              ret = TAP_IRSELECT;             break;
+       case XSV_IRCAPTURE:             ret = TAP_IRCAPTURE;            break;
+       case XSV_IRSHIFT:               ret = TAP_IRSHIFT;              break;
+       case XSV_IREXIT1:               ret = TAP_IREXIT1;              break;
+       case XSV_IRPAUSE:               ret = TAP_IRPAUSE;              break;
+       case XSV_IREXIT2:               ret = TAP_IREXIT2;              break;
+       case XSV_IRUPDATE:              ret = TAP_IRUPDATE;             break;
+       default:
+               LOG_ERROR( "UNKNOWN XSVF STATE 0x%02X", xsvf_state );
+               exit(1);
        }
-       jtag_add_pathmove(7, moves);
+
+       return ret;
 }
 
+
+
 int xsvf_register_commands(struct command_context_s *cmd_ctx)
 {
        register_command(cmd_ctx, NULL, "xsvf", handle_xsvf_command,
-               COMMAND_EXEC, "run xsvf <file>");
+               COMMAND_EXEC, "run xsvf <file> [virt2] [quiet]");
 
        return ERROR_OK;
 }
 
-int xsvf_read_buffer(int num_bits, int fd, u8* buf)
+static int xsvf_read_buffer(int num_bits, int fd, uint8_t* buf)
 {
        int num_bytes;
 
        for (num_bytes = (num_bits + 7) / 8; num_bytes > 0; num_bytes--)
        {
+               /* reverse the order of bytes as they are read sequentially from file */
                if (read(fd, buf + num_bytes - 1, 1) < 0)
                        return ERROR_XSVF_EOF;
        }
@@ -118,415 +183,836 @@ int xsvf_read_buffer(int num_bits, int fd, u8* buf)
        return ERROR_OK;
 }
 
-int xsvf_read_xstates(int fd, enum tap_state *path, int max_path, int *path_len)
-{
-       char c;
-       unsigned char uc;
-       
-       while ((read(fd, &c, 1) > 0) && (c == 0x12))
-       {
-               if (*path_len > max_path)
-               {
-                       LOG_WARNING("XSTATE path longer than max_path");
-                       break;
-               }
-               if (read(fd, &uc, 1) < 0)
-               {
-                       return ERROR_XSVF_EOF;
-               }
-               path[(*path_len)++] = xsvf_to_tap[uc];
-       }
-       
-       lseek(fd, -1, SEEK_CUR);
-       
-       return ERROR_OK;
-}
 
-int handle_xsvf_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
+static int handle_xsvf_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
 {
-       char c;
-       u8 buf4[4], buf2[2];
-       unsigned char uc, uc2;
-       unsigned int ui;
-       unsigned short us;
-
-       int do_abort = 0;
-       int unsupported = 0;
-       int tdo_mismatch = 0;
-       
-       int runtest_requires_tck = 0;
-       
-       int device = -1;        /* use -1 to indicate a "plain" xsvf file which accounts for additional devices in the scan chain, otherwise the device that should be affected */
+       uint8_t *dr_out_buf = NULL;                             /* from host to device (TDI) */
+       uint8_t *dr_in_buf = NULL;                              /* from device to host (TDO) */
+       uint8_t *dr_in_mask = NULL;
+
+       int xsdrsize = 0;
+       int xruntest = 0;                                       /* number of TCK cycles OR microseconds */
+       int xrepeat      = 0;                                   /* number of retries */
+
+       tap_state_t     xendir = TAP_IDLE;              /* see page 8 of the SVF spec, initial xendir to be TAP_IDLE */
+       tap_state_t xenddr = TAP_IDLE;
+
+       uint8_t                 opcode;
+       uint8_t         uc;
+       long            file_offset = 0;
+
+       int             loop_count = 0;
+       tap_state_t     loop_state = TAP_IDLE;
+       int             loop_clocks = 0;
+       int             loop_usecs = 0;
+
+       int             do_abort = 0;
+       int             unsupported = 0;
+       int             tdo_mismatch = 0;
+       int             result;
+       int             verbose = 1;
+       char*   filename;
+
+       int             runtest_requires_tck = 0;       /* a flag telling whether to clock TCK during waits, or simply sleep, controled by virt2 */
+
+
+       /* use NULL to indicate a "plain" xsvf file which accounts for
+          additional devices in the scan chain, otherwise the device
+          that should be affected
+       */
+       jtag_tap_t *tap = NULL;
 
        if (argc < 2)
        {
-               command_print(cmd_ctx, "usage: xsvf <device#|plain> <file> <variant>");
-               return ERROR_OK;
+               command_print(cmd_ctx, "usage: xsvf <device#|plain> <file> [<variant>] [quiet]");
+               return ERROR_FAIL;
        }
 
+       filename = args[1];             /* we mess with args starting point below, snapshot filename here */
+
        if (strcmp(args[0], "plain") != 0)
        {
-               device = strtoul(args[0], NULL, 0);
+               tap = jtag_tap_by_string( args[0] );
+               if (!tap )
+               {
+                       command_print( cmd_ctx, "Tap: %s unknown", args[0] );
+                       return ERROR_FAIL;
+               }
        }
 
-       if ((xsvf_fd = open(args[1], O_RDONLY)) < 0)
+       if ((xsvf_fd = open(filename, O_RDONLY)) < 0)
        {
-               command_print(cmd_ctx, "file %s not found", args[0]);
-               return ERROR_OK;
+               command_print(cmd_ctx, "file \"%s\" not found", filename);
+               return ERROR_FAIL;
        }
-       
+
+       /* if this argument is present, then interpret xruntest counts as TCK cycles rather than as usecs */
        if ((argc > 2) && (strcmp(args[2], "virt2") == 0))
        {
                runtest_requires_tck = 1;
+               --argc;
+               ++args;
+       }
+
+       if ((argc > 2) && (strcmp(args[2], "quiet") == 0))
+       {
+               verbose = 0;
        }
 
-       while (read(xsvf_fd, &c, 1) > 0)
+       LOG_USER("xsvf processing file: \"%s\"", filename);
+
+       while( read(xsvf_fd, &opcode, 1) > 0 )
        {
-               switch (c)
+               /* record the position of the just read opcode within the file */
+               file_offset = lseek(xsvf_fd, 0, SEEK_CUR) - 1;
+
+               switch (opcode)
                {
-                       case 0x00:      /* XCOMPLETE */
-                               LOG_DEBUG("XCOMPLETE");
-                               if (jtag_execute_queue() != ERROR_OK)
-                               {
-                                       tdo_mismatch = 1;
-                                       break;  
-                               }
+               case XCOMPLETE:
+                       LOG_DEBUG("XCOMPLETE");
+
+                       result = jtag_execute_queue();
+                       if (result != ERROR_OK)
+                       {
+                               tdo_mismatch = 1;
                                break;
-                       case 0x01:      /* XTDOMASK */
-                               LOG_DEBUG("XTDOMASK");
-                               if (dr_in_mask && (xsvf_read_buffer(xsdrsize, xsvf_fd, dr_in_mask) != ERROR_OK))
+                       }
+                       break;
+
+               case XTDOMASK:
+                       LOG_DEBUG("XTDOMASK");
+                       if (dr_in_mask && (xsvf_read_buffer(xsdrsize, xsvf_fd, dr_in_mask) != ERROR_OK))
+                               do_abort = 1;
+                       break;
+
+               case XRUNTEST:
+                       {
+                               uint8_t xruntest_buf[4];
+
+                               if (read(xsvf_fd, xruntest_buf, 4) < 0)
+                               {
                                        do_abort = 1;
-                               break;
-                       case 0x02:      /* XSIR */
-                               LOG_DEBUG("XSIR");
-                               if (read(xsvf_fd, &c, 1) < 0)
+                                       break;
+                               }
+
+                               xruntest = be_to_h_u32(xruntest_buf);
+                               LOG_DEBUG("XRUNTEST %d 0x%08X", xruntest, xruntest);
+                       }
+                       break;
+
+               case XREPEAT:
+                       {
+                               uint8_t myrepeat;
+
+                               if (read(xsvf_fd, &myrepeat, 1) < 0)
                                        do_abort = 1;
                                else
                                {
-                                       u8 *ir_buf = malloc((c + 7) / 8);
-                                       if (xsvf_read_buffer(c, xsvf_fd, ir_buf) != ERROR_OK)
-                                               do_abort = 1;
-                                       else
-                                       {
-                                               scan_field_t field;
-                                               field.device = device;
-                                               field.num_bits = c;
-                                               field.out_value = ir_buf;
-                                               field.out_mask = NULL;
-                                               field.in_value = NULL;
-                                               field.in_check_value = NULL;
-                                               field.in_check_mask = NULL;
-                                               field.in_handler = NULL;
-                                               field.in_handler_priv = NULL;
-                                               if (device == -1)
-                                                       jtag_add_plain_ir_scan(1, &field, TAP_PI);
-                                               else
-                                                       jtag_add_ir_scan(1, &field, TAP_PI);
-                                               if (jtag_execute_queue() != ERROR_OK)
-                                               {
-                                                       tdo_mismatch = 1;
-                                                       free(ir_buf);
-                                                       break;
-                                               }
-                                               if (xruntest)
-                                               {
-                                                       if (runtest_requires_tck)
-                                                               jtag_add_runtest(xruntest, xsvf_to_tap[xendir]);
-                                                       else
-                                                       {
-                                                               xsvf_add_statemove(TAP_RTI);
-                                                               jtag_add_sleep(xruntest);
-                                                               xsvf_add_statemove(xsvf_to_tap[xendir]);
-                                                       }
-                                               }
-                                               else if (xendir != 0xd) /* Pause-IR */
-                                                       xsvf_add_statemove(xsvf_to_tap[xendir]);
-                                       }
-                                       free(ir_buf);
+                                       xrepeat = myrepeat;
+                                       LOG_DEBUG("XREPEAT %d", xrepeat );
                                }
-                               break;
-                       case 0x03:      /* XSDR */
-                               LOG_DEBUG("XSDR");
+                       }
+                       break;
+
+               case XSDRSIZE:
+                       {
+                               uint8_t xsdrsize_buf[4];
+
+                               if (read(xsvf_fd, xsdrsize_buf, 4) < 0)
+                               {
+                                       do_abort = 1;
+                                       break;
+                               }
+
+                               xsdrsize = be_to_h_u32(xsdrsize_buf);
+                               LOG_DEBUG("XSDRSIZE %d", xsdrsize);
+
+                               if ( dr_out_buf ) free(dr_out_buf);
+                               if ( dr_in_buf)   free(dr_in_buf);
+                               if ( dr_in_mask)  free(dr_in_mask);
+
+                               dr_out_buf = malloc((xsdrsize + 7) / 8);
+                               dr_in_buf = malloc((xsdrsize + 7) / 8);
+                               dr_in_mask = malloc((xsdrsize + 7) / 8);
+                       }
+                       break;
+
+               case XSDR:              /* these two are identical except for the dr_in_buf */
+               case XSDRTDO:
+                       {
+                               int limit = xrepeat;
+                               int     matched = 0;
+                               int attempt;
+
+                               const char* op_name = (opcode == XSDR ? "XSDR" : "XSDRTDO");
+
                                if (xsvf_read_buffer(xsdrsize, xsvf_fd, dr_out_buf) != ERROR_OK)
+                               {
                                        do_abort = 1;
-                               else
+                                       break;
+                               }
+
+                               if (opcode == XSDRTDO)
+                               {
+                                       if (xsvf_read_buffer(xsdrsize, xsvf_fd, dr_in_buf)  != ERROR_OK )
+                                       {
+                                               do_abort = 1;
+                                               break;
+                                       }
+                               }
+
+                               if (limit < 1)
+                                       limit = 1;
+
+                               LOG_DEBUG("%s %d", op_name, xsdrsize);
+
+                               for( attempt=0; attempt<limit;  ++attempt )
                                {
                                        scan_field_t field;
-                                       field.device = device;
+
+                                       if ( attempt>0 )
+                                       {
+                                               /* perform the XC9500 exception handling sequence shown in xapp067.pdf and
+                                                  illustrated in psuedo code at end of this file.  We start from state
+                                                  DRPAUSE:
+                                                  go to Exit2-DR
+                                                  go to Shift-DR
+                                                  go to Exit1-DR
+                                                  go to Update-DR
+                                                  go to Run-Test/Idle
+
+                                                  This sequence should be harmless for other devices, and it
+                                                  will be skipped entirely if xrepeat is set to zero.
+                                               */
+
+                                               static tap_state_t exception_path[] = {
+                                                       TAP_DREXIT2,
+                                                       TAP_DRSHIFT,
+                                                       TAP_DREXIT1,
+                                                       TAP_DRUPDATE,
+                                                       TAP_IDLE,
+                                               };
+
+                                               jtag_add_pathmove( DIM(exception_path), exception_path );
+
+                                               if (verbose)
+                                                       LOG_USER("%s mismatch, xsdrsize=%d retry=%d", op_name, xsdrsize, attempt);
+                                       }
+
+                                       field.tap = tap;
                                        field.num_bits = xsdrsize;
                                        field.out_value = dr_out_buf;
-                                       field.out_mask = NULL;
-                                       field.in_value = NULL;
-                                       jtag_set_check_value(&field, dr_in_buf, dr_in_mask, NULL);
-                                       if (device == -1)
-                                               jtag_add_plain_dr_scan(1, &field, TAP_PD);
+                                       field.in_value = calloc(CEIL(field.num_bits, 8), 1);
+
+                                       if (tap == NULL)
+                                               jtag_add_plain_dr_scan(1, &field, jtag_set_end_state(TAP_DRPAUSE));
                                        else
-                                               jtag_add_dr_scan(1, &field, TAP_PD);
-                                       if (jtag_execute_queue() != ERROR_OK)
-                                       {
-                                               tdo_mismatch = 1;
-                                               break;  
-                                       }
-                                       if (xruntest)
+                                               jtag_add_dr_scan(1, &field, jtag_set_end_state(TAP_DRPAUSE));
+
+                                       jtag_check_value_mask(&field, dr_in_buf, dr_in_mask);
+
+                                       free(field.in_value);
+
+
+                                       /* LOG_DEBUG("FLUSHING QUEUE"); */
+                                       result = jtag_execute_queue();
+                                       if (result == ERROR_OK)
                                        {
-                                               if (runtest_requires_tck)
-                                                       jtag_add_runtest(xruntest, xsvf_to_tap[xenddr]);
-                                               else
-                                               {
-                                                       xsvf_add_statemove(TAP_RTI);
-                                                       jtag_add_sleep(xruntest);
-                                                       xsvf_add_statemove(xsvf_to_tap[xenddr]);
-                                               }
+                                               matched = 1;
+                                               break;
                                        }
-                                       else if (xendir != 0x6) /* Pause-DR */
-                                               xsvf_add_statemove(xsvf_to_tap[xenddr]);
                                }
-                               break;
-                       case 0x04:      /* XRUNTEST */
-                               LOG_DEBUG("XRUNTEST");
-                               if (read(xsvf_fd, buf4, 4) < 0)
-                                       do_abort = 1;
-                               else
+
+                               if (!matched)
                                {
-                                       xruntest = be_to_h_u32(buf4);
+                                       LOG_USER( "%s mismatch", op_name);
+                                       tdo_mismatch = 1;
+                                       break;
                                }
-                               break;
-                       case 0x07:      /* XREPEAT */
-                               LOG_DEBUG("XREPEAT");
-                               if (read(xsvf_fd, &c, 1) < 0)
-                                       do_abort = 1;
-                               else
+
+                               /* See page 19 of XSVF spec regarding opcode "XSDR" */
+                               if (xruntest)
                                {
-                                       xrepeat = c;
+                                       jtag_add_statemove(TAP_IDLE);
+
+                                       if (runtest_requires_tck)
+                                               jtag_add_clocks(xruntest);
+                                       else
+                                               jtag_add_sleep(xruntest);
                                }
-                               break;
-                       case 0x08:      /* XSDRSIZE */
-                               LOG_DEBUG("XSDRSIZE");
-                               if (read(xsvf_fd, buf4, 4) < 0)
-                                       do_abort = 1;
-                               else
+                               else if (xendir != TAP_DRPAUSE) /* we are already in TAP_DRPAUSE */
+                                       jtag_add_statemove(xenddr);
+                       }
+                       break;
+
+               case XSETSDRMASKS:
+                       LOG_ERROR("unsupported XSETSDRMASKS\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRINC:
+                       LOG_ERROR("unsupported XSDRINC\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRB:
+                       LOG_ERROR("unsupported XSDRB\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRC:
+                       LOG_ERROR("unsupported XSDRC\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRE:
+                       LOG_ERROR("unsupported XSDRE\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRTDOB:
+                       LOG_ERROR("unsupported XSDRTDOB\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRTDOC:
+                       LOG_ERROR("unsupported XSDRTDOC\n");
+                       unsupported = 1;
+                       break;
+
+               case XSDRTDOE:
+                       LOG_ERROR("unsupported XSDRTDOE\n");
+                       unsupported = 1;
+                       break;
+
+               case XSTATE:
+                       {
+                               tap_state_t     mystate;
+                               uint8_t                 uc;
+
+                               if (read(xsvf_fd, &uc, 1) < 0)
                                {
-                                       xsdrsize = be_to_h_u32(buf4);
-                                       free(dr_out_buf);
-                                       free(dr_in_buf);
-                                       free(dr_in_mask);
-                                       dr_out_buf = malloc((xsdrsize + 7) / 8);
-                                       dr_in_buf = malloc((xsdrsize + 7) / 8);
-                                       dr_in_mask = malloc((xsdrsize + 7) / 8);
-                               }
-                               break;
-                       case 0x09:      /* XSDRTDO */
-                               LOG_DEBUG("XSDRTDO");
-                               if (xsvf_read_buffer(xsdrsize, xsvf_fd, dr_out_buf) != ERROR_OK)
                                        do_abort = 1;
-                               else
+                                       break;
+                               }
+
+                               mystate = xsvf_to_tap(uc);
+
+                               LOG_DEBUG("XSTATE 0x%02X %s", uc, tap_state_name(mystate) );
+
+                               /*      there is no need for the lookahead code that was here since we
+                                       queue up the jtag commands anyway.  This is a simple way to handle
+                                       the XSTATE.
+                               */
+
+                               if ( jtag_add_statemove( mystate ) != ERROR_OK )
                                {
-                                       if (xsvf_read_buffer(xsdrsize, xsvf_fd, dr_in_buf) != ERROR_OK)
-                                               do_abort = 1;
-                                       else
-                                       {
-                                               scan_field_t field;
-                                               field.device = device;
-                                               field.num_bits = xsdrsize;
-                                               field.out_value = dr_out_buf;
-                                               field.out_mask = NULL;
-                                               field.in_value = NULL;
-                                               jtag_set_check_value(&field, dr_in_buf, dr_in_mask, NULL);
-                                               if (device == -1)
-                                                       jtag_add_plain_dr_scan(1, &field, TAP_PD);
-                                               else
-                                                       jtag_add_dr_scan(1, &field, TAP_PD);
-                                               if (jtag_execute_queue() != ERROR_OK)
-                                               {
-                                                       tdo_mismatch = 1;
-                                                       break;  
-                                               }
-                                               if (xruntest)
-                                               {
-                                                       if (runtest_requires_tck)
-                                                               jtag_add_runtest(xruntest, xsvf_to_tap[xenddr]);
-                                                       else
-                                                       {
-                                                               xsvf_add_statemove(TAP_RTI);
-                                                               jtag_add_sleep(xruntest);
-                                                               xsvf_add_statemove(xsvf_to_tap[xenddr]);
-                                                       }
-                                               }
-                                               else if (xendir != 0x6) /* Pause-DR */
-                                                       xsvf_add_statemove(xsvf_to_tap[xenddr]);
-                                       }
+                                       /*      For special states known as stable states
+                                               (Test-Logic-Reset, Run-Test/Idle, Pause-DR, Pause- IR),
+                                               an XSVF interpreter follows predefined TAP state paths
+                                               when the starting state is a stable state and when the
+                                               XSTATE specifies a new stable state (see the STATE
+                                               command in the [Ref 5] for the TAP state paths between
+                                               stable states). For non-stable states, XSTATE should
+                                               specify a state that is only one TAP state transition
+                                               distance from the current TAP state to avoid undefined
+                                               TAP state paths. A sequence of multiple XSTATE commands
+                                               can be issued to transition the TAP through a specific
+                                               state path.
+                                       */
+
+                                       LOG_ERROR("XSTATE %s is not reachable from current state %s in one clock cycle",
+                                               tap_state_name(mystate),
+                                               tap_state_name(cmd_queue_cur_state)
+                                               );
                                }
+                       }
+                       break;
+
+               case XENDIR:
+
+                       if (read(xsvf_fd, &uc, 1) < 0)
+                       {
+                               do_abort = 1;
                                break;
-                       case 0x0a:      /* XSETDRMASKS */
-                               LOG_ERROR("unsupported XSETSDRMASKS\n");
-                               unsupported = 1;
-                               break;
-                       case 0x0b:      /* XSDRINC */
-                               LOG_ERROR("unsupported XSDRINC\n");
-                               unsupported = 1;
-                               break;
-                       case 0x0c:      /* XSDRB */
-                               unsupported = 1;
-                               break;
-                       case 0x0d:      /* XSDRC */
-                               unsupported = 1;
-                               break;
-                       case 0x0e:      /* XSDRE */
-                               unsupported = 1;
-                               break;
-                       case 0x0f:      /* XSDRTDOB */
+                       }
+
+                       /* see page 22 of XSVF spec */
+                       if ( uc == 0 )
+                               xendir = TAP_IDLE;
+                       else if ( uc == 1 )
+                               xendir = TAP_IRPAUSE;
+                       else
+                       {
+                               LOG_ERROR("illegial XENDIR argument: 0x%02X", uc);
                                unsupported = 1;
                                break;
-                       case 0x10:      /* XSDRTDOB */
-                               unsupported = 1;
+                       }
+
+                       LOG_DEBUG("XENDIR 0x%02X %s", uc, tap_state_name(xendir));
+                       break;
+
+               case XENDDR:
+
+                       if (read(xsvf_fd, &uc, 1) < 0)
+                       {
+                               do_abort = 1;
                                break;
-                       case 0x11:      /* XSDRTDOB */
+                       }
+
+                       /* see page 22 of XSVF spec */
+                       if ( uc == 0 )
+                               xenddr = TAP_IDLE;
+                       else if ( uc == 1 )
+                               xenddr = TAP_DRPAUSE;
+                       else
+                       {
+                               LOG_ERROR("illegial XENDDR argument: 0x%02X", uc);
                                unsupported = 1;
                                break;
-                       case 0x12:      /* XSTATE */
-                               LOG_DEBUG("XSTATE");
-                               if (read(xsvf_fd, &uc, 1) < 0)
-                                       do_abort = 1;
-                               else
+                       }
+
+                       LOG_DEBUG("XENDDR %02X %s", uc, tap_state_name(xenddr));
+                       break;
+
+               case XSIR:
+               case XSIR2:
+                       {
+                               uint8_t short_buf[2];
+                               uint8_t*        ir_buf;
+                               int bitcount;
+                               tap_state_t my_end_state = xruntest ? TAP_IDLE : xendir;
+
+                               if ( opcode == XSIR )
                                {
-                                       enum tap_state *path = calloc(XSTATE_MAX_PATH, 4);
-                                       int path_len = 1;
-                                       path[0] = xsvf_to_tap[uc];
-                                       if (xsvf_read_xstates(xsvf_fd, path, XSTATE_MAX_PATH, &path_len) != ERROR_OK)
-                                               do_abort = 1;
-                                       else
+                                       /* one byte bitcount */
+                                       if (read(xsvf_fd, short_buf, 1) < 0)
                                        {
-                                               jtag_add_pathmove(path_len, path);
+                                               do_abort = 1;
+                                               break;
                                        }
-                                       free(path);
+                                       bitcount = short_buf[0];
+                                       LOG_DEBUG("XSIR %d", bitcount);
                                }
-                               break;
-                       case 0x13:      /* XENDIR */
-                               LOG_DEBUG("XENDIR");
-                               if (read(xsvf_fd, &c, 1) < 0)
-                                       do_abort = 1;
                                else
                                {
-                                       if (c == 0)
-                                               xendir = 1;
-                                       else if (c == 1)
-                                               xendir = 0xd;
-                                       else
+                                       if (read(xsvf_fd, short_buf, 2) < 0)
                                        {
-                                               LOG_ERROR("unknown XENDIR endstate");
-                                               unsupported = 1;
+                                               do_abort = 1;
+                                               break;
                                        }
+                                       bitcount = be_to_h_u16(short_buf);
+                                       LOG_DEBUG("XSIR2 %d", bitcount);
                                }
-                               break;
-                       case 0x14:      /* XENDDR */
-                               LOG_DEBUG("XENDDR");
-                               if (read(xsvf_fd, &c, 1) < 0)
+
+                               ir_buf = malloc((bitcount+7) / 8);
+
+                               if (xsvf_read_buffer(bitcount, xsvf_fd, ir_buf) != ERROR_OK)
                                        do_abort = 1;
                                else
                                {
-                                       if (c == 0)
-                                               xenddr = 1;
-                                       else if (c == 1)
-                                               xenddr = 0x6;
+                                       scan_field_t field;
+
+                                       field.tap = tap;
+                                       field.num_bits = bitcount;
+                                       field.out_value = ir_buf;
+
+                                       field.in_value = NULL;
+
+
+                                       
+
+                                       if (tap == NULL)
+                                               jtag_add_plain_ir_scan(1, &field, my_end_state);
                                        else
+                                               jtag_add_ir_scan(1, &field, my_end_state);
+
+                                       if (xruntest)
                                        {
-                                               LOG_ERROR("unknown XENDDR endstate");
-                                               unsupported = 1;
+                                               if (runtest_requires_tck)
+                                                       jtag_add_clocks(xruntest);
+                                               else
+                                                       jtag_add_sleep(xruntest);
                                        }
-                               }
-                               break;
-                       case 0x15:      /* XSIR2 */
-                               LOG_DEBUG("XSIR2");
-                               if (read(xsvf_fd, buf2, 2) < 0)
-                                       do_abort = 1;
-                               else
-                               {
-                                       u8 *ir_buf;
-                                       us = be_to_h_u16(buf2);
-                                       ir_buf = malloc((us + 7) / 8);
-                                       if (xsvf_read_buffer(us, xsvf_fd, ir_buf) != ERROR_OK)
-                                               do_abort = 1;
-                                       else
+
+                                       /* Note that an -irmask of non-zero in your config file
+                                        * can cause this to fail.  Setting -irmask to zero cand work
+                                        * around the problem.
+                                        */
+
+                                       /* LOG_DEBUG("FLUSHING QUEUE"); */
+                                       result = jtag_execute_queue();
+                                       if (result != ERROR_OK)
                                        {
-                                               scan_field_t field;
-                                               field.device = device;
-                                               field.num_bits = us;
-                                               field.out_value = ir_buf;
-                                               field.out_mask = NULL;
-                                               field.in_value = NULL;
-                                               field.in_check_value = NULL;
-                                               field.in_check_mask = NULL;
-                                               field.in_handler = NULL;
-                                               field.in_handler_priv = NULL;
-                                               if (device == -1)
-                                                       jtag_add_plain_ir_scan(1, &field, xsvf_to_tap[xendir]);
-                                               else
-                                                       jtag_add_ir_scan(1, &field, xsvf_to_tap[xendir]);
+                                               tdo_mismatch = 1;
                                        }
-                                       free(ir_buf);
                                }
-                               break;
-                       case 0x16:      /* XCOMMENT */
+                               free(ir_buf);
+                       }
+                       break;
+
+               case XCOMMENT:
+                       {
+                               unsigned int ndx = 0;
+                               char    comment[128];
+
                                do
                                {
-                                       if (read(xsvf_fd, &c, 1) < 0)
+                                       if (read(xsvf_fd, &uc, 1) < 0)
                                        {
                                                do_abort = 1;
                                                break;
                                        }
-                               } while (c != 0);
-                               break;
-                       case 0x17:      /* XWAIT */
-                               LOG_DEBUG("XWAIT");
-                               if ((read(xsvf_fd, &uc, 1) < 0) || (read(xsvf_fd, &uc2, 1) < 0) || (read(xsvf_fd, buf4, 4) < 0))
+
+                                       if ( ndx < sizeof(comment)-1 )
+                                               comment[ndx++] = uc;
+
+                               } while (uc != 0);
+
+                               comment[sizeof(comment)-1] = 0;         /* regardless, terminate */
+                               if (verbose)
+                                       LOG_USER("# %s", comment);
+                       }
+                       break;
+
+               case XWAIT:
+                       {
+                               /* expected in stream:
+                                  XWAIT <uint8_t wait_state> <uint8_t end_state> <uint32_t usecs>
+                               */
+
+                               uint8_t wait;
+                               uint8_t end;
+                               uint8_t delay_buf[4];
+
+                               tap_state_t wait_state;
+                               tap_state_t end_state;
+                               int     delay;
+
+                               if ( read(xsvf_fd, &wait, 1) < 0
+                                 || read(xsvf_fd, &end, 1) < 0
+                                 || read(xsvf_fd, delay_buf, 4) < 0)
+                               {
                                        do_abort = 1;
+                                       break;
+                               }
+
+                               wait_state = xsvf_to_tap(wait);
+                               end_state  = xsvf_to_tap(end);
+                               delay      = be_to_h_u32(delay_buf);
+
+                               LOG_DEBUG("XWAIT %s %s usecs:%d", tap_state_name(wait_state), tap_state_name(end_state), delay);
+
+                               if (runtest_requires_tck && wait_state == TAP_IDLE )
+                               {
+                                       jtag_add_runtest(delay, end_state);
+                               }
                                else
                                {
-                                       xsvf_add_statemove(xsvf_to_tap[uc]);
-                                       ui = be_to_h_u32(buf4);
-                                       jtag_add_sleep(ui);
-                                       xsvf_add_statemove(xsvf_to_tap[uc2]);
+                                       jtag_add_statemove( wait_state );
+                                       jtag_add_sleep(delay);
+                                       jtag_add_statemove( end_state );
                                }
-                               break;
-                       default:
-                               LOG_ERROR("unknown xsvf command (0x%2.2x)\n", c);
-                               unsupported = 1;
+                       }
+                       break;
+
+               case XWAITSTATE:
+                       {
+                               /* expected in stream:
+                                  XWAITSTATE <uint8_t wait_state> <uint8_t end_state> <uint32_t clock_count> <uint32_t usecs>
+                               */
+
+                               uint8_t  clock_buf[4];
+                               uint8_t         usecs_buf[4];
+                               uint8_t wait;
+                               uint8_t end;
+                               tap_state_t wait_state;
+                               tap_state_t end_state;
+                               int clock_count;
+                               int usecs;
+
+                               if ( read(xsvf_fd, &wait, 1) < 0
+                                ||  read(xsvf_fd, &end, 1) < 0
+                                ||  read(xsvf_fd, clock_buf, 4) < 0
+                                ||  read(xsvf_fd, usecs_buf, 4) < 0 )
+                               {
+                                       do_abort = 1;
+                                       break;
+                               }
+
+                               wait_state = xsvf_to_tap( wait );
+                               end_state  = xsvf_to_tap( end );
+
+                               clock_count = be_to_h_u32(clock_buf);
+                               usecs       = be_to_h_u32(usecs_buf);
+
+                               LOG_DEBUG("XWAITSTATE %s %s clocks:%i usecs:%i",
+                                       tap_state_name(wait_state),
+                                       tap_state_name(end_state),
+                                       clock_count, usecs);
+
+                               /* the following states are 'stable', meaning that they have a transition
+                                * in the state diagram back to themselves.  This is necessary because we will
+                                * be issuing a number of clocks in this state.  This set of allowed states is also
+                                * determined by the SVF RUNTEST command's allowed states.
+                                */
+                               if (wait_state != TAP_IRPAUSE && wait_state != TAP_DRPAUSE && wait_state != TAP_RESET && wait_state != TAP_IDLE)
+                               {
+                                       LOG_ERROR("illegal XWAITSTATE wait_state: \"%s\"", tap_state_name( wait_state ));
+                                       unsupported = 1;
+                               }
+
+                               jtag_add_statemove( wait_state );
+
+                               jtag_add_clocks( clock_count );
+
+                               jtag_add_sleep( usecs );
+
+                               jtag_add_statemove( end_state );
+                       }
+                       break;
+
+               case LCOUNT:
+                       {
+                               /* expected in stream:
+                                  LCOUNT <uint32_t loop_count>
+                               */
+                               uint8_t  count_buf[4];
+
+                               if ( read(xsvf_fd, count_buf, 4) < 0 )
+                               {
+                                       do_abort = 1;
+                                       break;
+                               }
+
+                               loop_count = be_to_h_u32(count_buf);
+                               LOG_DEBUG("LCOUNT %d", loop_count);
+                       }
+                       break;
+
+               case LDELAY:
+                       {
+                               /* expected in stream:
+                                  LDELAY <uint8_t wait_state> <uint32_t clock_count> <uint32_t usecs_to_sleep>
+                               */
+                               uint8_t state;
+                               uint8_t  clock_buf[4];
+                               uint8_t  usecs_buf[4];
+
+                               if ( read(xsvf_fd, &state, 1) < 0
+                                 || read(xsvf_fd, clock_buf, 4) < 0
+                                 ||     read(xsvf_fd, usecs_buf, 4) < 0 )
+                               {
+                                       do_abort = 1;
+                                       break;
+                               }
+
+                               loop_state  = xsvf_to_tap(state);
+                               loop_clocks = be_to_h_u32(clock_buf);
+                               loop_usecs  = be_to_h_u32(usecs_buf);
+
+                               LOG_DEBUG("LDELAY %s clocks:%d usecs:%d", tap_state_name(loop_state), loop_clocks, loop_usecs);
+                       }
+                       break;
+
+               /* LSDR is more like XSDRTDO than it is like XSDR.  It uses LDELAY which
+                * comes with clocks !AND! sleep requirements.
+                */
+               case LSDR:
+                       {
+                               int limit = loop_count;
+                               int matched = 0;
+                               int attempt;
+
+                               LOG_DEBUG("LSDR");
+
+                               if ( xsvf_read_buffer(xsdrsize, xsvf_fd, dr_out_buf) != ERROR_OK
+                                 || xsvf_read_buffer(xsdrsize, xsvf_fd, dr_in_buf) != ERROR_OK )
+                               {
+                                       do_abort = 1;
+                                       break;
+                               }
+
+                               if (limit < 1)
+                                       limit = 1;
+
+                               for( attempt=0; attempt<limit;  ++attempt )
+                               {
+                                       scan_field_t field;
+
+                                       jtag_add_statemove( loop_state );
+                                       jtag_add_clocks(loop_clocks);
+                                       jtag_add_sleep(loop_usecs);
+
+                                       field.tap = tap;
+                                       field.num_bits = xsdrsize;
+                                       field.out_value = dr_out_buf;
+                                       field.in_value = calloc(CEIL(field.num_bits, 8), 1);
+
+                                       if (attempt > 0 && verbose)
+                                               LOG_USER("LSDR retry %d", attempt);
+
+                                       if (tap == NULL)
+                                               jtag_add_plain_dr_scan(1, &field, jtag_set_end_state(TAP_DRPAUSE));
+                                       else
+                                               jtag_add_dr_scan(1, &field, jtag_set_end_state(TAP_DRPAUSE));
+
+                                       jtag_check_value_mask(&field, dr_in_buf, dr_in_mask);
+
+                                       free(field.in_value);
+
+
+                                       /* LOG_DEBUG("FLUSHING QUEUE"); */
+                                       result = jtag_execute_queue();
+                                       if (result == ERROR_OK)
+                                       {
+                                               matched = 1;
+                                               break;
+                                       }
+                               }
+
+                               if (!matched )
+                               {
+                                       LOG_USER( "LSDR mismatch" );
+                                       tdo_mismatch = 1;
+                                       break;
+                               }
+                       }
+                       break;
+
+               case XTRST:
+                       {
+                               uint8_t trst_mode;
+
+                               if (read(xsvf_fd, &trst_mode, 1) < 0)
+                               {
+                                       do_abort = 1;
+                                       break;
+                               }
+
+                               switch( trst_mode )
+                               {
+                               case XTRST_ON:
+                                       jtag_add_reset(1, 0);
+                                       break;
+                               case XTRST_OFF:
+                               case XTRST_Z:
+                                       jtag_add_reset(0, 0);
+                                       break;
+                               case XTRST_ABSENT:
+                                       break;
+                               default:
+                                       LOG_ERROR( "XTRST mode argument (0x%02X) out of range", trst_mode );
+                                       do_abort = 1;
+                               }
+                       }
+                       break;
+
+               default:
+                       LOG_ERROR("unknown xsvf command (0x%02X)\n", uc);
+                       unsupported = 1;
                }
 
                if (do_abort || unsupported || tdo_mismatch)
+               {
+                       LOG_DEBUG("xsvf failed, setting taps to reasonable state");
+
+                       /* upon error, return the TAPs to a reasonable state */
+                       jtag_add_statemove( TAP_IDLE );
+                       jtag_execute_queue();
                        break;
+               }
        }
-       
+
        if (tdo_mismatch)
        {
-               command_print(cmd_ctx, "TDO mismatch, aborting");
-               return ERROR_OK;
+               command_print(cmd_ctx, "TDO mismatch, somewhere near offset %lu in xsvf file, aborting",
+                                         file_offset );
+
+
+               return ERROR_FAIL;
        }
 
        if (unsupported)
        {
-               command_print(cmd_ctx, "unsupported xsvf command encountered, aborting");
-               return ERROR_OK;
+               off_t offset = lseek(xsvf_fd, 0, SEEK_CUR) - 1;
+               command_print(cmd_ctx,
+                               "unsupported xsvf command (0x%02X) at offset %jd, aborting",
+                               uc, (intmax_t)offset);
+               return ERROR_FAIL;
        }
 
        if (do_abort)
        {
-               command_print(cmd_ctx, "premature end detected, aborting");
-               return ERROR_OK;
+               command_print(cmd_ctx, "premature end of xsvf file detected, aborting");
+               return ERROR_FAIL;
        }
-       
+
        if (dr_out_buf)
                free(dr_out_buf);
-       
+
        if (dr_in_buf)
                free(dr_in_buf);
-       
+
        if (dr_in_mask)
                free(dr_in_mask);
 
        close(xsvf_fd);
-       
+
        command_print(cmd_ctx, "XSVF file programmed successfully");
 
        return ERROR_OK;
 }
+
+
+#if 0   /* this comment style used to try and keep uncrustify from adding * at begin of line */
+
+PSUEDO-Code from Xilinx Appnote XAPP067.pdf:
+
+the following pseudo code clarifies the intent of the xrepeat support.  The
+flow given is for the entire processing of an SVF file, not an XSVF file.
+No idea if this is just for the XC9500/XL/XV devices or all Xilinx parts.
+
+"Pseudo-Code Algorithm for SVF-Based ISP"
+
+1. Go to Test-Logic-Reset state
+2. Go to Run-Test Idle state
+3. Read SVF record
+
+4. if SIR record then
+          go to Shift-IR state
+          Scan in <TDI value>
+
+5. else if SDR record then
+          set <repeat count> to 0
+          store <TDI value> as <current TDI value>
+          store <TDO value> as <current TDO value>
+6. go to Shift-DR state
+          scan in <current TDI value>
+          if <current TDO value> is specified then
+                  if <current TDO value> does not equal <actual TDO value> then
+                          if <repeat count> > 32 then
+                                  LOG ERROR
+                                  go to Run-Test Idle state
+                                  go to Step 3
+                          end if
+                          go to Pause-DR
+                          go to Exit2-DR
+                          go to Shift-DR
+                          go to Exit1-DR
+                          go to Update-DR
+                          go to Run-Test/Idle
+                          increment <repeat count> by 1
+                          pause <current pause time> microseconds
+                          go to Step 6)
+                  end if
+          else
+                  go to Run-Test Idle state
+                  go to Step 3
+          endif
+else if RUNTEST record then
+   pause tester for <TCK value> microseconds
+   store <TCK value> as <current pause time>
+end if
+
+#endif