git.gag.com Git - fw/altos/blob - src/drivers/ao_ads124s0x.c

   1 /*
   2  * Copyright © 2019 Bdale Garbee <bdale@gag.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  */
  14
  15 #include <ao.h>
  16 #include "ao_ads124s0x.h"
  17
  18 #define DEBUG_LOW       1
  19 #define DEBUG_HIGH      2
  20
  21 #define DEBUG           0
  22
  23 #if DEBUG
  24 #define PRINTD(l, ...) do { if (DEBUG & (l)) { printf ("\r%5u %s: ", ao_tick_count, __func__); printf(__VA_ARGS__); flush(); } } while(0)
  25 #else
  26 #define PRINTD(l,...)
  27 #endif
  28
  29 struct ao_ads124s0x_sample      ao_ads124s0x_current;
  30
  31 static void
  32 ao_ads124s0x_start(void) {
  33         ao_spi_get_bit(AO_ADS124S0X_SPI_CS_PORT,
  34                        AO_ADS124S0X_SPI_CS_PIN,
  35                        AO_ADS124S0X_SPI_BUS,
  36                        AO_ADS124S0X_SPI_SPEED);
  37 }
  38
  39 static void
  40 ao_ads124s0x_stop(void) {
  41         ao_spi_put_bit(AO_ADS124S0X_SPI_CS_PORT,
  42                        AO_ADS124S0X_SPI_CS_PIN,
  43                        AO_ADS124S0X_SPI_BUS);
  44 }
  45
  46 /*
  47 static uint8_t
  48 ao_ads124s0x_reg_read(uint8_t addr)
  49 {
  50         uint8_t d[2];
  51
  52         d[0] = addr | AO_ADS124S0X_RREG;
  53         d[1] = 0;
  54         ao_ads124s0x_start();
  55         ao_spi_duplex(d, d, 2, AO_ADS124S0X_SPI_BUS);
  56         ao_ads124s0x_stop();
  57
  58         PRINTD(DEBUG_LOW, "read %x = %x\n", addr, d);
  59
  60         return d[1];
  61 }
  62
  63 static void
  64 ao_ads124s0x_reg_write(uint8_t addr, uint8_t value)
  65 {
  66         uint8_t d[3];
  67
  68         PRINTD(DEBUG_LOW, "write %x %x\n", addr, value);
  69         d[0] = addr | AO_ADS124S0X_WREG;
  70         d[1] = 0;
  71         d[2] = value;
  72         ao_ads124s0x_start();
  73         ao_spi_send(d, 3, AO_ADS124S0X_SPI_BUS);
  74         ao_ads124s0x_stop();
  75
  76 #if DEBUG & DEBUG_LOW
  77         d[0] = addr | AO_ADS124S0X_RREG
  78         d[1] = 0;
  79         ao_ads124s0x_start();
  80         ao_spi_duplex(d, d, 2, AO_ADS124S0X_SPI_BUS);
  81         ao_ads124s0x_stop();
  82         PRINTD(DEBUG_LOW, "readback %x %x\n", d[0], d[1]);
  83 #endif
  84 }
  85 */
  86
  87 // FIXME
  88 //      We need to be in continuous conversion mode, and use the WREG
  89 //      command to set the next conversion input while reading each
  90 //      which I don't see an example for elsewhere?
  91
  92 static void
  93 ao_ads124s0x_setup(void)
  94 {
  95         uint8_t d[20];
  96
  97 /*      we have nowhere to report this error to since ao_sensor_errors is
  98         normally part of ao_flight?
  99
 100         uint8_t devid = ao_ads124s0x_reg_read(AO_ADS124S0X_ID);
 101         if (devid != AO_ADS124S0X_ID_ADS124S06)
 102                 ao_sensor_errors = 1;
 103 */
 104
 105         /* 1ksps each across 4 inputs using full duplex ala 9.5.4.3 */
 106
 107         d[0] = AO_ADS124S0X_INPMUX | AO_ADS124S0X_WREG;
 108         d[1] = 8;       /* write 8 registers starting with INPMUX */
 109         d[2] = 0x0c;    /* input mux AIN0 relative to AINCOM */
 110         d[3] = 0x00;    /* default first conversion delay, pga disabled */
 111         d[4] = 0x1e;    /* gchop disabled, internal clock, continuous
 112                            conversion, low-latency filter, 4000 SPS */
 113         d[5] = 0x00;    /* ref monitor disabled, ref buffers bypassed, ref
 114                            set to REFP0/REFN0, internal reference off */
 115         d[6] = 0x00;    /* pga otuput rail, low side power switch, excitation
 116                            current source all off */
 117         d[7] = 0xff;    /* idac1 and idac2 disconnected */
 118         d[8] = 0x00;    /* all vbias disconnected */
 119         d[9] = 0x10;    /* sys monitor off, spi timeout disabled, crc disabled,
 120                            prepending status byte disabled */
 121         ao_ads124s0x_start();
 122         ao_spi_send(d, 10, AO_ADS124S0X_SPI_BUS);
 123         ao_ads124s0x_stop();
 124
 125         /* start conversions */
 126
 127         d[0] = AO_ADS124S0X_START;
 128         ao_ads124s0x_start();
 129         ao_spi_send(d, 1, AO_ADS124S0X_SPI_BUS);
 130         ao_ads124s0x_stop();
 131 }
 132
 133 static void
 134 ao_ads124s0x(void)
 135 {
 136         ao_ads124s0x_setup();
 137 /*
 138         for (;;) {
 139                 ao_ads124s0x_value(&ao_ads124s0x_current);
 140                 ao_arch_critical(
 141                         AO_DATA_PRESENT(AO_DATA_ADS124S0X);
 142                         AO_DATA_WAIT();
 143                         );
 144         }
 145 */
 146 }
 147
 148 static struct ao_task ao_ads124s0x_task;
 149
 150 static void
 151 ao_ads124s0x_dump(void)                 // FIXME
 152 {
 153         printf ("ADS124S0X value %d %d %d %d\n",
 154                 ao_ads124s0x_current.ain0,
 155                 ao_ads124s0x_current.ain1,
 156                 ao_ads124s0x_current.ain2,
 157                 ao_ads124s0x_current.ain3);
 158 }
 159
 160 const struct ao_cmds ao_ads124s0x_cmds[] = {
 161         { ao_ads124s0x_dump,    "I\0Display ADS124S0X data" },
 162         { 0, NULL },
 163 };
 164
 165 void
 166 ao_ads124s0x_init(void)
 167 {
 168         ao_cmd_register(ao_ads124s0x_cmds);
 169         ao_spi_init_cs(AO_ADS124S0X_SPI_CS_PORT,
 170                 (1 << AO_ADS124S0X_SPI_CS_PIN));
 171
 172         ao_add_task(&ao_ads124s0x_task, ao_ads124s0x, "ads124s0x");
 173 }