diff options
| -rw-r--r-- | accel.c | 68 |
1 files changed, 35 insertions, 33 deletions
@@ -21,12 +21,6 @@ OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ -/* We use two freefall wakup thresholds: - * 1) Shake detection with >= 127 (~2g), actual value is ignored - * 2) Horizon detection with <= 60 (~1g) for 100ms, if the interrupt is - * asserted the actual value has to be read to determine the horizon - */ - #include "common.h" #include <stdio.h> @@ -40,6 +34,13 @@ THE SOFTWARE. #include "i2c.h" #include "accel.h" +/* configuration */ +/* horizon trigger threshold ~0.75g and duration 15*10ms */ +#define HORIZON_THRESHOLD 48 +#define HORIZON_DURATION 15 +/* shake detect trashold ~2g */ +#define SHAKE_THRESHOLD 120 + /* device address */ #define LIS302DL 0b00111000 /* registers */ @@ -54,6 +55,9 @@ THE SOFTWARE. #define LIS302DL_FFWUCFG2 0x34 #define LIS302DL_FFWUTHS2 0x36 +/* bit positions in registers, see chip docs */ +#define ZHIE 5 + static int8_t zval; static uint8_t shakeCount = 0; @@ -104,6 +108,8 @@ void accelInit () { void accelStart () { assert (state == STOPPED); state = START_REQUEST; + /* make sure the current horizon is read at startup */ + enableWakeup (WAKE_ACCEL_HORIZON); } void accelProcess () { @@ -122,23 +128,22 @@ void accelProcess () { } /* set up ff_wu_1 (horizon detection) */ - case STARTING_A: { - puts ("setting thresh wu1"); - /* threshold 60 (~1g), duration 100ms (10 steps at 10ms) */ - static uint8_t data[] = {0b00111100, 0b1010}; - if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_FFWUTHS1, data, - sizeof (data)/sizeof (*data))) { - state = STARTING_B; + case STARTING_A: + if (shouldWakeup (WAKE_I2C)) { + disableWakeup (WAKE_I2C); + static uint8_t data[] = {HORIZON_THRESHOLD, HORIZON_DURATION}; + if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_FFWUTHS1, data, + sizeof (data)/sizeof (*data))) { + state = STARTING_B; + } } break; - } case STARTING_B: if (shouldWakeup (WAKE_I2C)) { disableWakeup (WAKE_I2C); - puts ("setting events wu1"); - /* or events, enable interrupt on z low event */ - static uint8_t data[] = {0b00010000}; + /* enable interrupt on z high event */ + static uint8_t data[] = {1 << ZHIE}; if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_FFWUCFG1, data, sizeof (data)/sizeof (*data))) { state = STARTING_C; @@ -147,23 +152,22 @@ void accelProcess () { break; /* set up ff_wu_2 (shake detection) */ - case STARTING_C: { - puts ("setting thresh wu2"); - /* threshold 127 (~2g) (duration, next register, not modified) */ - static uint8_t data[] = {0b01111111}; - if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_FFWUTHS2, data, - sizeof (data)/sizeof (*data))) { - state = STARTING_D; + case STARTING_C: + if (shouldWakeup (WAKE_I2C)) { + disableWakeup (WAKE_I2C); + static uint8_t data[] = {SHAKE_THRESHOLD}; + if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_FFWUTHS2, data, + sizeof (data)/sizeof (*data))) { + state = STARTING_D; + } } break; - } case STARTING_D: if (shouldWakeup (WAKE_I2C)) { disableWakeup (WAKE_I2C); - puts ("setting events wu2"); - /* or events, enable interrupt on z high event (+/-) */ - static uint8_t data[] = {0b00100000}; + /* or events, enable interrupt on z high event */ + static uint8_t data[] = {1 << ZHIE}; if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_FFWUCFG2, data, sizeof (data)/sizeof (*data))) { state = STARTING_E; @@ -174,7 +178,6 @@ void accelProcess () { case STARTING_E: if (shouldWakeup (WAKE_I2C)) { disableWakeup (WAKE_I2C); - puts ("setting int"); /* push-pull, low-active, FF_WU_1 on int1, FF_WU_2 on int2 */ static uint8_t data[] = {0b10010001}; if (twRequest (TWM_WRITE, LIS302DL, LIS302DL_CTRLREG3, data, @@ -187,7 +190,6 @@ void accelProcess () { case STARTING_F: if (shouldWakeup (WAKE_I2C)) { disableWakeup (WAKE_I2C); - puts ("ffwu setup done"); state = IDLE; } break; @@ -212,12 +214,12 @@ void accelProcess () { //assert (twr.status == TWST_OK); if (zval >= 0) { - if (horizonSign == HORIZON_NEG) { + if (horizonSign != HORIZON_POS) { horizonChanged = true; } horizonSign = HORIZON_POS; } else { - if (horizonSign == HORIZON_POS) { + if (horizonSign != HORIZON_NEG) { horizonChanged = true; } horizonSign = HORIZON_NEG; @@ -240,7 +242,7 @@ horizon accelGetHorizon (bool * const changed) { } uint8_t accelGetShakeCount () { - return shakeCount; + return shakeCount/2; } void accelResetShakeCount () { |