git.gag.com Git - fw/altos/blob - src/drivers/ao_ads131a0x.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_exti.h>
  17 #include "ao_ads131a0x.h"
  18
  19 #define DEBUG_LOW       1
  20 #define DEBUG_HIGH      2
  21
  22 #define DEBUG           0
  23
  24 #if DEBUG
  25 #define PRINTD(l, ...) do { if (DEBUG & (l)) { printf ("\r%5u %s: ", ao_tick_count, __func__); printf(__VA_ARGS__); flush(); } } while(0)
  26 #else
  27 #define PRINTD(l,...)
  28 #endif
  29
  30 struct ao_ads131a0x_sample      ao_ads131a0x_current;
  31 uint8_t         nextchan = 0;
  32 uint8_t         ao_ads131a0x_drdy;
  33
  34 static void
  35 ao_ads131a0x_start(void) {
  36         ao_spi_get_bit(AO_ADS131A0X_SPI_CS_PORT,
  37                        AO_ADS131A0X_SPI_CS_PIN,
  38                        AO_ADS131A0X_SPI_BUS,
  39                        AO_ADS131A0X_SPI_SPEED);
  40 }
  41
  42 static void
  43 ao_ads131a0x_stop(void) {
  44         ao_spi_put_bit(AO_ADS131A0X_SPI_CS_PORT,
  45                        AO_ADS131A0X_SPI_CS_PIN,
  46                        AO_ADS131A0X_SPI_BUS);
  47 }
  48
  49 static uint8_t
  50 ao_ads131a0x_reg_read(uint8_t addr)
  51 {
  52         uint8_t d[15];
  53
  54         d[0] = addr | (AO_ADS131A0X_RREG >> 8);
  55         d[1] = 0;
  56         d[2] = 0;
  57         d[3] = 0;
  58         d[4] = 0;
  59         d[5] = 0;
  60         d[6] = 0;
  61         d[7] = 0;
  62         d[8] = 0;
  63         d[9] = 0;
  64         d[10] = 0;
  65         d[11] = 0;
  66         d[12] = 0;
  67         d[13] = 0;
  68         d[14] = 0;
  69         ao_ads131a0x_start();
  70         ao_spi_send(d, 15, AO_ADS131A0X_SPI_BUS);
  71         ao_ads131a0x_stop();
  72
  73         /* data isn't actually returned until the next frame */
  74         d[0] = AO_ADS131A0X_NULL >> 8;
  75         d[1] = AO_ADS131A0X_NULL & 0xff;
  76         ao_ads131a0x_start();
  77         ao_spi_duplex(d, d, 15, AO_ADS131A0X_SPI_BUS);
  78         ao_ads131a0x_stop();
  79
  80         /* first byte is register number, second byte is the data */
  81         PRINTD(DEBUG_LOW, "read %x = %x\n", addr, d[1]);
  82
  83         return d[1];
  84 }
  85
  86 /*
  87 static void
  88 ao_ads131a0x_reg_write(uint8_t addr, uint8_t value)
  89 {
  90         uint8_t d[15];
  91
  92         PRINTD(DEBUG_LOW, "write %x %x\n", addr, value);
  93         d[0] = addr | (AO_ADS131A0X_WREG >> 8);
  94         d[1] = value;
  95         d[2] = 0;
  96         d[3] = 0;
  97         d[4] = 0;
  98         d[5] = 0;
  99         d[6] = 0;
 100         d[7] = 0;
 101         d[8] = 0;
 102         d[9] = 0;
 103         d[10] = 0;
 104         d[11] = 0;
 105         d[12] = 0;
 106         d[13] = 0;
 107         d[14] = 0;
 108         ao_ads131a0x_start();
 109         ao_spi_send(d, 15, AO_ADS131A0X_SPI_BUS);
 110         ao_ads131a0x_stop();
 111 }
 112 */
 113
 114 static void
 115 ao_ads131a0x_isr(void)
 116 {
 117         ao_ads131a0x_drdy = 1;
 118         ao_wakeup(&ao_ads131a0x_drdy);
 119 }
 120
 121 static void
 122 ao_ads131a0x_setup(void)
 123 {
 124         uint8_t d[20];
 125
 126         ao_delay(1);
 127
 128         ao_gpio_set(AO_ADS131A0X_RESET_PORT, AO_ADS131A0X_RESET_PIN, 1);
 129
 130         ao_delay(1);
 131
 132         /* send unlock command?  why, if we've not locked it? */
 133
 134         uint8_t devid = ao_ads131a0x_reg_read(AO_ADS131A0X_ID_MSB);
 135         if (devid != AO_ADS131A0X_ID_ADS131A04)
 136                 ao_panic(AO_PANIC_SELF_TEST_ADS);
 137
 138         ao_exti_setup(AO_ADS131A0X_DRDY_PORT, AO_ADS131A0X_DRDY_PIN,
 139                 AO_EXTI_MODE_FALLING|AO_EXTI_PRIORITY_HIGH,
 140                 ao_ads131a0x_isr);
 141
 142         /* register writes use top 16 bits of each 24-bit word */
 143
 144         d[0] = AO_ADS131A0X_A_SYS_CFG | (AO_ADS131A0X_WREGS >> 8);
 145         d[1] = 8;       /* write (n-1) registers starting with A_SYS_CFG */
 146         d[2] = 0;
 147
 148         d[3] = 0x78;    /* A_SYS_CFG - charge pump off, high res, 4.0V ref,
 149                            internal ref on, 5/95% fault thresholds */
 150         d[4] = 0x00;    /* D_SYS_CFG - watchdog off, crc on device words,
 151                            shortest done and hi-z delays, non-fixed size,
 152                            crc disabled */
 153         d[5] = 0;
 154
 155         d[6] = 0x02;    /* CLK1 - crystal osc on, ICLK = CLKIN / 2 */
 156         d[7] = 0x20;    /* CLK2 - MOD = ICLK / 2, DATA = MOD / 4096 */
 157         d[8] = 0;
 158
 159         d[9] = 0x0f;    /* ADC_ENA - all channels powered up */
 160         d[10] = 0;      /* reserved */
 161         d[11] = 0;
 162
 163         d[12] = 0x00;   /* ADC1 - gain = 1 */
 164         d[13] = 0x00;   /* ADC2 - gain = 1 */
 165         d[14] = 0;
 166
 167         d[15] = 0x00;   /* ADC3 - gain = 1 */
 168         d[16] = 0x00;   /* ADC4 - gain = 1 */
 169         d[17] = 0;
 170
 171         ao_ads131a0x_start();
 172         ao_spi_send(d, 18, AO_ADS131A0X_SPI_BUS);
 173         ao_ads131a0x_stop();
 174
 175         /* start conversions */
 176
 177         d[0] = AO_ADS131A0X_WAKEUP >> 8;
 178         d[1] = AO_ADS131A0X_WAKEUP & 0xff;
 179         d[2] = 0;
 180         ao_ads131a0x_start();
 181         ao_spi_send(d, 3, AO_ADS131A0X_SPI_BUS);
 182         ao_ads131a0x_stop();
 183
 184         /* documented initialization sends the LOCK command here, but I can
 185            see no value in doing that! */
 186 }
 187
 188 static void
 189 ao_ads131a0x(void)
 190 {
 191         uint8_t d[15];
 192
 193         ao_ads131a0x_setup();
 194
 195         ao_exti_enable(AO_ADS131A0X_DRDY_PORT, AO_ADS131A0X_DRDY_PIN);
 196
 197         for (;;) {
 198                 ao_arch_block_interrupts();
 199                 ao_ads131a0x_drdy = 0;
 200                 while (ao_ads131a0x_drdy == 0)
 201                         ao_sleep(&ao_ads131a0x_drdy);
 202                 ao_arch_release_interrupts();
 203
 204                 d[0] = AO_ADS131A0X_NULL >> 8;
 205                 d[1] = AO_ADS131A0X_NULL & 0xff;
 206                 d[2] = 0;
 207                 d[3] = 0;
 208                 d[4] = 0;
 209                 d[5] = 0;
 210                 d[6] = 0;
 211                 d[7] = 0;
 212                 d[8] = 0;
 213                 d[9] = 0;
 214                 d[10] = 0;
 215                 d[11] = 0;
 216                 d[12] = 0;
 217                 d[13] = 0;
 218                 d[14] = 0;
 219
 220                 ao_ads131a0x_start();
 221                 ao_spi_duplex(d, d, 15, AO_ADS131A0X_SPI_BUS);
 222                 ao_ads131a0x_stop();
 223
 224                 ao_ads131a0x_current.ain[0] =
 225                         d[3] << 16 | d[4] << 8 | d[5];
 226                 ao_ads131a0x_current.ain[1] =
 227                         d[6] << 16 | d[7] << 8 | d[8];
 228                 ao_ads131a0x_current.ain[2] =
 229                         d[9] << 16 | d[10] << 8 | d[11];
 230                 ao_ads131a0x_current.ain[3] =
 231                         d[12] << 16 | d[13] << 8 | d[14];
 232
 233                 // FIXME
 234                 //       we need to log this data somewhere
 235
 236                 ao_ads131a0x_drdy = 0;
 237         }
 238 }
 239
 240 static struct ao_task ao_ads131a0x_task;
 241
 242 static void
 243 ao_ads131a0x_dump(void)
 244 {
 245         static int done;
 246
 247         if (!done) {
 248                 done = 1;
 249                 ao_add_task(&ao_ads131a0x_task, ao_ads131a0x, "ads131a0x");
 250         }
 251
 252         printf ("ADS131A0X value %d %d %d %d\n",
 253                 ao_ads131a0x_current.ain[0],
 254                 ao_ads131a0x_current.ain[1],
 255                 ao_ads131a0x_current.ain[2],
 256                 ao_ads131a0x_current.ain[3]);
 257 }
 258
 259 const struct ao_cmds ao_ads131a0x_cmds[] = {
 260         { ao_ads131a0x_dump,    "I\0Display ADS131A0X data" },
 261         { 0, NULL },
 262 };
 263
 264 void
 265 ao_ads131a0x_init(void)
 266 {
 267         ao_cmd_register(ao_ads131a0x_cmds);
 268
 269         ao_enable_output(AO_ADS131A0X_RESET_PORT, AO_ADS131A0X_RESET_PIN, 0);
 270
 271         ao_spi_init_cs(AO_ADS131A0X_SPI_CS_PORT,
 272                 (1 << AO_ADS131A0X_SPI_CS_PIN));
 273
 274 //      ao_add_task(&ao_ads131a0x_task, ao_ads131a0x, "ads131a0x");
 275 }