/*-------------------------------------------------------------------------
- _gptrget.c :- get value for a generic pointer
+ _gptrget.c :- get value for a generic pointer
Written By - Sandeep Dutta . sandeep.dutta@usa.net (1999)
- 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
+ This library is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Library General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.
-
- This program is distributed in the hope that it will be useful,
+
+ This library 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
+ GNU Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
along with this program; if not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
+
In other words, you are welcome to use, share and improve this program.
You are forbidden to forbid anyone else to use, share and improve
- what you give them. Help stamp out software-hoarding!
+ what you give them. Help stamp out software-hoarding!
-------------------------------------------------------------------------*/
-unsigned char _gptrget ()
+/* not all devices use P2 to page pdata memory, therefore __XPAGE was
+ introduced. On some targets __XPAGE itself is a paged SFR so it is
+ not safe for all platforms to set this. Furthermore some targets
+ can be configured to behave differently for movx @dptr vs. movx @Ri
+ (don't drive high byte of address bus for movx @Ri only) */
+#define USE_PDATA_PAGING_REGISTER 0
+
+__sbit __at (0xF7) B_7;
+__sbit __at (0xF6) B_6;
+__sbit __at (0xF5) B_5;
+
+/* the return value is expected to be in acc, and not in the standard
+ * location dpl. Therefore we choose return type void here: */
+#if defined DSDCC_MODEL_HUGE
+void
+_gptrget (char *gptr) __naked
+{
+/* This is the banked version with pointers up to 23 bits.
+ B cannot be trashed */
+
+ gptr; /* hush the compiler */
+
+ __asm
+ ;
+ ; depending on the pointer type acc. to SDCCsymt.h
+ ;
+ jb _B_7,codeptr$ ; >0x80 code ; 3
+ jnb _B_6,xdataptr$ ; <0x40 far ; 3
+
+ mov dph,r0 ; save r0 independant of regbank ; 2
+ mov r0,dpl ; use only low order address ; 2
+
+ jb _B_5,pdataptr$ ; >0x60 pdata ; 3
+ ;
+ ; Pointer to data space
+ ;
+ mov a,@r0 ; 1
+ dataptrrestore$:
+ mov r0,dph ; restore r0 ; 2
+ mov dph,#0 ; restore dph ; 2
+ ret ; 1
+ ;
+ ; pointer to external stack or pdata
+ ;
+ pdataptr$:
+ movx a,@r0 ; 1
+ sjmp dataptrrestore$ ; 2
+ ;
+ ; pointer to code area
+ ;
+ codeptr$:
+ ; implementation for SiLabs C8051F12x
+ mov a,b ; 2
+ anl a,#0x03 ; 2
+ swap a ; 1
+ push _PSBANK ; 2
+ anl _PSBANK,#0x0F ; 3
+ orl _PSBANK,a ; 2
+
+ clr a ; 1
+ movc a,@a+dptr ; 1
+ pop _PSBANK ; 2
+ ret ; 1
+ ;
+ ; pointer to xternal data
+ ;
+ xdataptr$:
+ ; implementation for xram a16-a21 tied to P3
+ mov _P3,b ; 3
+
+ movx a,@dptr ; 1
+ ret ; 1
+ ;===
+ ;44 bytes
+ __endasm;
+}
+
+#elif defined DSDCC_MODEL_MEDIUM
+
+void
+_gptrget (char *gptr) __naked
+{
+/* This is the non-banked version with pointers up to 15 bits.
+ Assumes B is free to be used */
+
+ gptr; /* hush the compiler */
+
+ __asm
+ ;
+ ; depending on the pointer type acc. to SDCCsymt.h
+ ;
+ mov b,dph ; 3
+ jb _B_7,codeptr$ ; >0x80 code ; 3
+ jnb _B_6,xdataptr$ ; <0x40 far ; 3
+
+ mov b,r0 ; save r0 independant of regbank ; 2
+ mov r0,dpl ; use only low order address ; 2
+
+ jb _B_5,pdataptr$ ; >0x60 pdata ; 3
+ ;
+ ; Pointer to data space
+ ;
+ mov a,@r0 ; 1
+ mov r0,b ; restore r0 ; 2
+ ret ; 1
+ ;
+ ; pointer to xternal stack or pdata
+ ;
+ pdataptr$:
+ movx a,@r0 ; 1
+ mov r0,b ; restore r0 ; 2
+ ret ; 1
+ ;
+ ; pointer to code area, max 15 bits
+ ;
+ codeptr$:
+ ; 0x8000 <= dptr <= 0xFFFF
+ ; no need to AND dph and restore from B if hardware wraps code memory
+ anl dph,#0x7F ; 3
+ clr a ; 1
+ movc a,@a+dptr ; 1
+ mov dph,b ; 3
+ ret ; 1
+ ;
+ ; pointer to xternal data, max 14 bits
+ ;
+ xdataptr$:
+ ; 0 <= dptr <= 0x3FFF
+ movx a,@dptr ; 1
+ ret ; 1
+ ;===
+ ;35 bytes
+ __endasm;
+}
+
+#else
+
+void
+_gptrget (char *gptr) __naked
+{
+/* This is the new version with pointers up to 16 bits.
+ B cannot be trashed */
+
+ gptr; /* hush the compiler */
+
+ __asm
+ ;
+ ; depending on the pointer type acc. to SDCCsymt.h
+ ;
+ jb _B_7,codeptr$ ; >0x80 code ; 3
+ jnb _B_6,xdataptr$ ; <0x40 far ; 3
+
+ mov dph,r0 ; save r0 independant of regbank ; 2
+ mov r0,dpl ; use only low order address ; 2
+
+ jb _B_5,pdataptr$ ; >0x60 pdata ; 3
+ ;
+ ; Pointer to data space
+ ;
+ mov a,@r0 ; 1
+ dataptrrestore$:
+ mov r0,dph ; restore r0 ; 2
+ mov dph,#0 ; restore dph ; 2
+ ret ; 1
+ ;
+ ; pointer to xternal stack or pdata
+ ;
+ pdataptr$:
+ movx a,@r0 ; 1
+ sjmp dataptrrestore$ ; 2
+ ;
+ ; pointer to code area, max 16 bits
+ ;
+ codeptr$:
+ clr a ; 1
+ movc a,@a+dptr ; 1
+ ret ; 1
+ ;
+ ; pointer to xternal data, max 16 bits
+ ;
+ xdataptr$:
+ movx a,@dptr ; 1
+ ret ; 1
+ ;===
+ ;27 bytes
+ __endasm;
+}
+
+#endif
+
+#ifdef SDCC_ds390
+/* the return value is expected to be in acc/_ap, and not in the standard
+ * location dpl/dph. Therefore we choose return type void here: */
+
+void
+_gptrgetWord (unsigned *gptr)
{
- _asm
- ; save values passed
- xch a,r0
- push acc
- ;
- ; depending on the pointer type
- ;
- mov a,b
- jz 00001$
- dec a
- jz 00002$
- dec a
- jz 00003$
- dec a
- jz 00004$
- ;
- ; any other value for type
- ; return xFF
- mov a,#0xff
- sjmp 00005$
+ gptr; /* hush the compiler */
+
+ __asm
+ ;
+ ; depending on the pointer type acc. to SDCCsymt.h
+ ;
+ jb _B_7,00003$ ; >0x80 code
+ jnb _B_6,00002$ ; <0x40 far
+
+ mov dph,r0 ; save r0 independant of regbank
+ mov r0,dpl ; use only low order address
+
+ jb _B_5,00004$ ; >0x60 pdata
;
; Pointer to data space
- ;
- 00001$:
- mov r0,dpl ; use only low order address
- mov a,@r0
+ ;
+ mov _ap,@r0
+ inc r0
+ mov a,@r0
+ inc dpl
sjmp 00005$
;
; pointer to xternal data
;
00002$:
movx a,@dptr
- sjmp 00005$
+ mov _ap,a
+ inc dptr
+ movx a,@dptr
+ sjmp 00006$
;
; pointer to code area
-;
+;
00003$:
- clr a
+ clr a
movc a,@a+dptr
- sjmp 00005$
+ mov _ap,a
+ clr a
+ inc dptr
+ movc a,@a+dptr
+ sjmp 00006$
;
; pointer to xternal stack
;
00004$:
- mov r0,dpl
movx a,@r0
+ mov _ap,a
+ inc r0
+ movx a,@r0
+ inc dpl
;
; restore and return
;
- 00005$:
- mov r0,a
- pop acc
- xch a,r0
- _endasm ;
-
+ 00005$:
+ mov r0,dph ; restore r0
+ mov dph,#0 ; restore dph
+ 00006$:
+ xch a,_ap
+ __endasm;
+
}
+
+#endif
projects / fw / sdcc / blobdiff