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/*
* Copyright © 2019 Bdale Garbee <bdale@gag.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.
*/
#include <ao.h>
#include <ao_exti.h>
#include "ao_ads124s0x.h"
#define DEBUG_LOW 1
#define DEBUG_HIGH 2
#define DEBUG 0
#if DEBUG
#define PRINTD(l, ...) do { if (DEBUG & (l)) { printf ("\r%5u %s: ", ao_tick_count, __func__); printf(__VA_ARGS__); flush(); } } while(0)
#else
#define PRINTD(l,...)
#endif
struct ao_ads124s0x_sample ao_ads124s0x_current;
uint8_t nextchan = 0;
uint8_t ao_ads124s0x_drdy;
static void
ao_ads124s0x_start(void) {
ao_spi_get_bit(AO_ADS124S0X_SPI_CS_PORT,
AO_ADS124S0X_SPI_CS_PIN,
AO_ADS124S0X_SPI_BUS,
AO_ADS124S0X_SPI_SPEED);
}
static void
ao_ads124s0x_stop(void) {
ao_spi_put_bit(AO_ADS124S0X_SPI_CS_PORT,
AO_ADS124S0X_SPI_CS_PIN,
AO_ADS124S0X_SPI_BUS);
}
static uint8_t
ao_ads124s0x_reg_read(uint8_t addr)
{
uint8_t d[3];
d[0] = addr | AO_ADS124S0X_RREG;
d[1] = 0;
d[2] = 0;
ao_ads124s0x_start();
ao_spi_duplex(d, d, 3, AO_ADS124S0X_SPI_BUS);
ao_ads124s0x_stop();
PRINTD(DEBUG_LOW, "read %x = %x\n", addr, d[0]);
return d[2];
}
/*
static void
ao_ads124s0x_reg_write(uint8_t addr, uint8_t value)
{
uint8_t d[3];
PRINTD(DEBUG_LOW, "write %x %x\n", addr, value);
d[0] = addr | AO_ADS124S0X_WREG;
d[1] = 0;
d[2] = value;
ao_ads124s0x_start();
ao_spi_send(d, 3, AO_ADS124S0X_SPI_BUS);
ao_ads124s0x_stop();
}
*/
static void
ao_ads124s0x_isr(void)
{
ao_ads124s0x_drdy = 1;
ao_wakeup(&ao_ads124s0x_drdy);
}
static void
ao_ads124s0x_setup(void)
{
uint8_t d[20];
ao_delay(1);
ao_gpio_set(AO_ADS124S0X_RESET_PORT, AO_ADS124S0X_RESET_PIN, 1);
ao_delay(1);
uint8_t devid = ao_ads124s0x_reg_read(AO_ADS124S0X_ID);
if ((devid & 7) != AO_ADS124S0X_ID_ADS124S06)
ao_panic(AO_PANIC_SELF_TEST_ADS124S0X);
ao_exti_setup(AO_ADS124S0X_DRDY_PORT, AO_ADS124S0X_DRDY_PIN,
AO_EXTI_MODE_FALLING|AO_EXTI_PRIORITY_HIGH,
ao_ads124s0x_isr);
/* run converter at 4ksps so we can scan 4 channels at 1ksps using
full duplex ala datasheet section 9.5.4.3 */
d[0] = AO_ADS124S0X_INPMUX | AO_ADS124S0X_WREG;
d[1] = 8; /* write 8 registers starting with INPMUX */
d[2] = 0x0c; /* input mux AIN0 relative to AINCOM */
d[3] = 0x00; /* default first conversion delay, pga disabled */
d[4] = 0x1e; /* gchop disabled, internal clock, continuous
conversion, low-latency filter, 4000 SPS */
d[5] = 0x00; /* ref monitor disabled, ref buffers bypassed, ref
set to REFP0/REFN0, internal reference off */
d[6] = 0x00; /* pga otuput rail, low side power switch, excitation
current source all off */
d[7] = 0xff; /* idac1 and idac2 disconnected */
d[8] = 0x00; /* all vbias disconnected */
d[9] = 0x10; /* sys monitor off, spi timeout disabled, crc disabled,
prepending status byte disabled */
ao_ads124s0x_start();
ao_spi_send(d, 10, AO_ADS124S0X_SPI_BUS);
ao_ads124s0x_stop();
/* start conversions */
d[0] = AO_ADS124S0X_START;
ao_ads124s0x_start();
ao_spi_send(d, 1, AO_ADS124S0X_SPI_BUS);
ao_ads124s0x_stop();
}
static void
ao_ads124s0x(void)
{
uint8_t d[3], curchan;
ao_ads124s0x_setup();
ao_exti_enable(AO_ADS124S0X_DRDY_PORT, AO_ADS124S0X_DRDY_PIN);
for (;;) {
ao_arch_block_interrupts();
ao_ads124s0x_drdy = 0;
while (ao_ads124s0x_drdy == 0)
ao_sleep(&ao_ads124s0x_drdy);
ao_arch_release_interrupts();
curchan = nextchan;
nextchan = (nextchan + 1) % AO_ADS124S0X_CHANNELS;
d[0] = AO_ADS124S0X_INPMUX | AO_ADS124S0X_WREG;
d[1] = 1;
d[2] = nextchan << 4 | 0x0c; ; /* relative to AINCOM */
ao_ads124s0x_start();
ao_spi_duplex(d, d, 3, AO_ADS124S0X_SPI_BUS);
ao_ads124s0x_stop();
ao_ads124s0x_current.ain[curchan] =
d[0] << 16 | d[1] << 8 | d[2];
// FIXME
// If nextchan == 0, we have a complete set of inputs
// and we need to log them somewhere
ao_ads124s0x_drdy = 0;
}
}
static struct ao_task ao_ads124s0x_task;
static void
ao_ads124s0x_dump(void)
{
static int done;
if (!done) {
done = 1;
ao_add_task(&ao_ads124s0x_task, ao_ads124s0x, "ads124s0x");
}
printf ("ADS124S0X value %d %d %d %d\n",
ao_ads124s0x_current.ain[0],
ao_ads124s0x_current.ain[1],
ao_ads124s0x_current.ain[2],
ao_ads124s0x_current.ain[3]);
}
const struct ao_cmds ao_ads124s0x_cmds[] = {
{ ao_ads124s0x_dump, "I\0Display ADS124S0X data" },
{ 0, NULL },
};
void
ao_ads124s0x_init(void)
{
ao_cmd_register(ao_ads124s0x_cmds);
ao_enable_output(AO_ADS124S0X_RESET_PORT, AO_ADS124S0X_RESET_PIN, 0);
ao_spi_init_cs(AO_ADS124S0X_SPI_CS_PORT,
(1 << AO_ADS124S0X_SPI_CS_PIN));
// ao_add_task(&ao_ads124s0x_task, ao_ads124s0x, "ads124s0x");
}
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