lis2dw: add FIFO support

This commit is contained in:
Joey Castillo 2022-02-17 16:36:21 -05:00
parent deda65b313
commit 0c59c972e7
3 changed files with 78 additions and 22 deletions

View file

@ -24,17 +24,13 @@ static void cb_tick(void) {
if (!lis2dw_have_new_data()) return;
watch_set_indicator(WATCH_INDICATOR_SIGNAL);
lis2dw_reading raw_reading;
lis2dw_acceleration_measurement measurement = lis2dw_get_acceleration_measurement(&raw_reading);
printf("%f, %f, %f\n", measurement.x, measurement.y, measurement.z);
char buf[128];
sprintf(buf, "%f, %f, %f\n", measurement.x, measurement.y, measurement.z);
watch_debug_puts(buf);
lis2dw_fifo_t fifo;
bool overrun = lis2dw_read_fifo(&fifo);
printf("FIFO captured %d readings.\n", fifo.count);
if (overrun) printf("\tThere was an overrun!\n\n");
}
void app_init(void) {
watch_enable_debug_uart(460800); // this is glitchy now, but this enables a baud rate of 115200 when USB is disabled.
watch_enable_display();
watch_display_string("AC Strean", 0);
@ -45,12 +41,14 @@ void app_init(void) {
watch_enable_i2c();
lis2dw_begin();
lis2dw_set_data_rate(LIS2DW_DATA_RATE_25_HZ); // is this enough for training?
lis2dw_set_low_noise_mode(true); // consumes a little more power
lis2dw_set_low_power_mode(LIS2DW_LP_MODE_2); // lowest power 14-bit mode, 25 Hz is 3.5 µA @ 1.8V w/ low noise, 3µA without
lis2dw_set_low_noise_mode(true); // consumes a little more power
lis2dw_set_range(LIS2DW_CTRL6_VAL_RANGE_4G);
lis2dw_set_data_rate(LIS2DW_DATA_RATE_25_HZ); // is this enough for training?
watch_rtc_register_periodic_callback(cb_tick, 64);
lis2dw_enable_fifo();
watch_rtc_register_periodic_callback(cb_tick, 1);
}
void app_wake_from_backup(void) {

View file

@ -50,10 +50,10 @@ bool lis2dw_have_new_data(void) {
return retval & LIS2DW_STATUS_VAL_DRDY;
}
lis2dw_reading lis2dw_get_raw_reading(void) {
lis2dw_reading_t lis2dw_get_raw_reading(void) {
uint8_t buffer[6];
uint8_t reg = LIS2DW_REG_OUT_X_L | 0x80; // set high bit for consecutive reads
lis2dw_reading retval;
lis2dw_reading_t retval;
watch_i2c_send(LIS2DW_ADDRESS, &reg, 1);
watch_i2c_receive(LIS2DW_ADDRESS, (uint8_t *)&buffer, 6);
@ -68,8 +68,8 @@ lis2dw_reading lis2dw_get_raw_reading(void) {
return retval;
}
lis2dw_acceleration_measurement lis2dw_get_acceleration_measurement(lis2dw_reading *out_reading) {
lis2dw_reading reading = lis2dw_get_raw_reading();
lis2dw_acceleration_measurement_t lis2dw_get_acceleration_measurement(lis2dw_reading_t *out_reading) {
lis2dw_reading_t reading = lis2dw_get_raw_reading();
uint8_t range = lis2dw_get_range();
if (out_reading != NULL) *out_reading = reading;
@ -82,7 +82,7 @@ lis2dw_reading lis2dw_get_raw_reading(void) {
if (range == LIS2DW_RANGE_8_G) lsb_value = 16;
if (range == LIS2DW_RANGE_16_G) lsb_value = 48;
lis2dw_acceleration_measurement retval;
lis2dw_acceleration_measurement_t retval;
retval.x = lsb_value * ((float)reading.x / 64000.0);
retval.y = lsb_value * ((float)reading.y / 64000.0);
@ -104,7 +104,6 @@ lis2dw_range_t lis2dw_get_range(void) {
return (lis2dw_range_t)retval;
}
void lis2dw_set_data_rate(lis2dw_data_rate_t dataRate) {
uint8_t val = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & ~(0b1111 << 4);
uint8_t bits = dataRate << 4;
@ -137,3 +136,31 @@ void lis2dw_set_low_noise_mode(bool on) {
bool lis2dw_get_low_noise_mode(void) {
return (watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_CTRL1) & LIS2DW_CTRL6_VAL_LOW_NOISE) != 0;
}
inline void lis2dw_disable_fifo(void) {
watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_FIFO_CTRL, LIS2DW_FIFO_CTRL_MODE_OFF);
}
inline void lis2dw_enable_fifo(void) {
watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_FIFO_CTRL, LIS2DW_FIFO_CTRL_MODE_COLLECT_AND_STOP | LIS2DW_FIFO_CTRL_FTH);
}
bool lis2dw_read_fifo(lis2dw_fifo_t *fifo_data) {
uint8_t temp = watch_i2c_read8(LIS2DW_ADDRESS, LIS2DW_REG_FIFO_SAMPLE);
bool overrun = !!(temp & LIS2DW_FIFO_SAMPLE_OVERRUN);
uint8_t buffer[6];
fifo_data->count = temp & LIS2DW_FIFO_SAMPLE_COUNT;
for(int i = 0; i < fifo_data->count; i++) {
watch_i2c_receive(LIS2DW_ADDRESS, (uint8_t *)&buffer, 6);
fifo_data->readings[i] = lis2dw_get_raw_reading();
}
return overrun;
}
void lis2dw_clear_fifo(void) {
watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_FIFO_CTRL, LIS2DW_FIFO_CTRL_MODE_OFF);
watch_i2c_write8(LIS2DW_ADDRESS, LIS2DW_REG_FIFO_CTRL, LIS2DW_FIFO_CTRL_MODE_COLLECT_AND_STOP | LIS2DW_FIFO_CTRL_FTH);
}

View file

@ -32,13 +32,18 @@ typedef struct {
int16_t x;
int16_t y;
int16_t z;
} lis2dw_reading;
} lis2dw_reading_t;
typedef struct {
float x;
float y;
float z;
} lis2dw_acceleration_measurement;
} lis2dw_acceleration_measurement_t;
typedef struct {
int8_t count;
lis2dw_reading_t readings[32];
} lis2dw_fifo_t;
typedef enum {
LIS2DW_DATA_RATE_POWERDOWN = 0,
@ -60,6 +65,14 @@ typedef enum {
LIS2DW_MODE_ON_DEMAND = 0b10,
} lis2dw_mode_t;
typedef enum {
LIS2DW_FIFO_MODE_OFF = 0b000,
LIS2DW_FIFO_MODE_COLLECT_AND_STOP = 0b001,
LIS2DW_FIFO_MODE_CONTINUOUS_TO_FIFO = 0b011,
LIS2DW_FIFO_MODE_BYPASS_TO_CONTINUOUS = 0b100,
LIS2DW_FIFO_MODE_COLLECT_CONTINUOUS = 0b110,
} lis2dw_fifo_mode_t;
typedef enum {
LIS2DW_LP_MODE_1 = 0b00, // 12-bit
LIS2DW_LP_MODE_2 = 0b01, // 14-bit
@ -177,7 +190,17 @@ typedef enum {
#define LIS2DW_REG_OUT_Z_H 0x2D
#define LIS2DW_REG_FIFO_CTRL 0x2E
#define LIS2DW_REG_FIFO_SRC 0x2F
#define LIS2DW_FIFO_CTRL_MODE_OFF (LIS2DW_FIFO_MODE_OFF << 5)
#define LIS2DW_FIFO_CTRL_MODE_COLLECT_AND_STOP (LIS2DW_FIFO_MODE_COLLECT_AND_STOP << 5)
#define LIS2DW_FIFO_CTRL_MODE_CONTINUOUS_TO_FIFO (LIS2DW_FIFO_MODE_CONTINUOUS_TO_FIFO << 5)
#define LIS2DW_FIFO_CTRL_MODE_BYPASS_TO_CONTINUOUS (LIS2DW_FIFO_MODE_BYPASS_TO_CONTINUOUS << 5)
#define LIS2DW_FIFO_CTRL_MODE_COLLECT_CONTINUOUS (LIS2DW_FIFO_MODE_COLLECT_CONTINUOUS << 5)
#define LIS2DW_FIFO_CTRL_FTH (0b00011111)
#define LIS2DW_REG_FIFO_SAMPLE 0x2F
#define LIS2DW_FIFO_SAMPLE_THRESHOLD (1 << 7)
#define LIS2DW_FIFO_SAMPLE_OVERRUN (1 << 6)
#define LIS2DW_FIFO_SAMPLE_COUNT (0b00111111)
#define LIS2DW_REG_TAP_THS_X 0x30
#define LIS2DW_REG_TAP_THS_Y 0x31
@ -242,9 +265,9 @@ uint8_t lis2dw_get_device_id(void);
bool lis2dw_have_new_data(void);
lis2dw_reading lis2dw_get_raw_reading(void);
lis2dw_reading_t lis2dw_get_raw_reading(void);
lis2dw_acceleration_measurement lis2dw_get_acceleration_measurement(lis2dw_reading *out_reading);
lis2dw_acceleration_measurement_t lis2dw_get_acceleration_measurement(lis2dw_reading_t *out_reading);
void lis2dw_set_range(lis2dw_range_t range);
@ -262,4 +285,12 @@ void lis2dw_set_low_noise_mode(bool on);
bool lis2dw_get_low_noise_mode(void);
void lis2dw_disable_fifo(void);
void lis2dw_enable_fifo(void);
bool lis2dw_read_fifo(lis2dw_fifo_t *fifo_data);
void lis2dw_clear_fifo(void);
#endif // LIS2DW_H