static uint8_t ao_mpu6000_configured;
static void
-ao_mpu6000_isr(void)
+ao_mpu6000_write(uint8_t addr, uint8_t *data, uint8_t len)
{
- ao_exti_disable(&AO_MPU6000_INT_PORT, AO_MPU6000_INT_PIN);
- ao_mpu6000_wake = 1;
- ao_wakeup(&ao_mpu6000_wake);
+ ao_i2c_get(AO_MPU6000_I2C_INDEX);
+ ao_i2c_start(AO_MPU6000_I2C_INDEX, MPU6000_ADDR_WRITE);
+ ao_i2c_send(&addr, 1, AO_MPU6000_I2C_INDEX, FALSE);
+ ao_i2c_send(data, len, AO_MPU6000_I2C_INDEX, TRUE);
+ ao_i2c_put(AO_MPU6000_I2C_INDEX);
}
static void
-ao_mpu6000_write(uint8_t addr, uint8_t *data, uint8_t len)
+ao_mpu6000_reg_write(uint8_t addr, uint8_t value)
{
+ uint8_t d[2] = { addr, value };
ao_i2c_get(AO_MPU6000_I2C_INDEX);
ao_i2c_start(AO_MPU6000_I2C_INDEX, MPU6000_ADDR_WRITE);
- ao_i2c_send(&addr, 1, AO_MPU6000_I2C_INDEX, FALSE);
- ao_i2c_send(data, len, AO_MPU6000_I2C_INDEX, TRUE);
+ ao_i2c_send(d, 2, AO_MPU6000_I2C_INDEX, TRUE);
ao_i2c_put(AO_MPU6000_I2C_INDEX);
}
static void
-ao_mpu6000_read(uint8_t addr, uint8_t *data, uint8_t len)
+ao_mpu6000_read(uint8_t addr, void *data, uint8_t len)
{
ao_i2c_get(AO_MPU6000_I2C_INDEX);
ao_i2c_start(AO_MPU6000_I2C_INDEX, MPU6000_ADDR_WRITE);
ao_i2c_put(AO_MPU6000_I2C_INDEX);
}
+static uint8_t
+ao_mpu6000_reg_read(uint8_t addr)
+{
+ uint8_t value;
+ ao_i2c_get(AO_MPU6000_I2C_INDEX);
+ ao_i2c_start(AO_MPU6000_I2C_INDEX, MPU6000_ADDR_WRITE);
+ ao_i2c_send(&addr, 1, AO_MPU6000_I2C_INDEX, FALSE);
+ ao_i2c_start(AO_MPU6000_I2C_INDEX, MPU6000_ADDR_READ);
+ ao_i2c_recv(&value, 1, AO_MPU6000_I2C_INDEX, TRUE);
+ ao_i2c_put(AO_MPU6000_I2C_INDEX);
+ return value;
+}
+
+static void
+ao_mpu6000_sample(struct ao_mpu6000_sample *sample)
+{
+ uint16_t *d = (uint16_t *) sample;
+ int i = sizeof (*sample) / 2;
+
+ ao_mpu6000_read(MPU6000_ACCEL_XOUT_H, sample, sizeof (*sample));
+ /* byte swap (sigh) */
+ while (i--) {
+ uint16_t t = *d;
+ *d++ = (t >> 8) | (t << 8);
+ }
+}
+
+#define G 981 /* in cm/s² */
+
+static int16_t /* cm/s² */
+ao_mpu6000_accel(int16_t v)
+{
+ return (int16_t) ((v * (int32_t) (16.0 * 980.665 + 0.5)) / 32767);
+}
+
+static int16_t /* deg*10/s */
+ao_mpu6000_gyro(int16_t v)
+{
+ return (int16_t) ((v * (int32_t) 20000) / 32767);
+}
+
+static uint8_t
+ao_mpu6000_accel_check(int16_t normal, int16_t test, char *which)
+{
+ int16_t diff = test - normal;
+
+ if (diff < MPU6000_ST_ACCEL(16) / 2) {
+ printf ("%s accel self test value too small (normal %d, test %d)\n",
+ which, normal, test);
+ return FALSE;
+ }
+ if (diff > MPU6000_ST_ACCEL(16) * 2) {
+ printf ("%s accel self test value too large (normal %d, test %d)\n",
+ which, normal, test);
+ return FALSE;
+ }
+ return TRUE;
+}
+
+static uint8_t
+ao_mpu6000_gyro_check(int16_t normal, int16_t test, char *which)
+{
+ int16_t diff = test - normal;
+
+ if (diff < 0)
+ diff = -diff;
+ if (diff < MPU6000_ST_GYRO(2000) / 2) {
+ printf ("%s gyro self test value too small (normal %d, test %d)\n",
+ which, normal, test);
+ return FALSE;
+ }
+ if (diff > MPU6000_ST_GYRO(2000) * 2) {
+ printf ("%s gyro self test value too large (normal %d, test %d)\n",
+ which, normal, test);
+ return FALSE;
+ }
+ return TRUE;
+}
+
static void
ao_mpu6000_setup(void)
{
+ struct ao_mpu6000_sample normal_mode, test_mode;
+ int t;
+
if (ao_mpu6000_configured)
return;
- /* Enable the EXTI interrupt for the appropriate pin */
- ao_enable_port(AO_MPU6000_INT_PORT);
- ao_exti_setup(&AO_MPU6000_INT_PORT, AO_MPU6000_INT_PIN,
- AO_EXTI_MODE_FALLING, ao_mpu6000_isr);
+ /* Reset the whole chip */
+
+ ao_mpu6000_reg_write(MPU6000_PWR_MGMT_1,
+ (1 << MPU6000_PWR_MGMT_1_DEVICE_RESET));
+ while (ao_mpu6000_reg_read(MPU6000_PWR_MGMT_1) &
+ (1 << MPU6000_PWR_MGMT_1_DEVICE_RESET))
+ ao_yield();
+
+ /* Reset signal conditioning */
+ ao_mpu6000_reg_write(MPU6000_USER_CONTROL,
+ (0 << MPU6000_USER_CONTROL_FIFO_EN) |
+ (0 << MPU6000_USER_CONTROL_I2C_MST_EN) |
+ (0 << MPU6000_USER_CONTROL_I2C_IF_DIS) |
+ (0 << MPU6000_USER_CONTROL_FIFO_RESET) |
+ (0 << MPU6000_USER_CONTROL_I2C_MST_RESET) |
+ (1 << MPU6000_USER_CONTROL_SIG_COND_RESET));
+
+ while (ao_mpu6000_reg_read(MPU6000_USER_CONTROL) & (1 << MPU6000_USER_CONTROL_SIG_COND_RESET))
+ ao_yield();
+
+ /* Reset signal paths */
+ ao_mpu6000_reg_write(MPU6000_SIGNAL_PATH_RESET,
+ (1 << MPU6000_SIGNAL_PATH_RESET_GYRO_RESET) |
+ (1 << MPU6000_SIGNAL_PATH_RESET_ACCEL_RESET) |
+ (1 << MPU6000_SIGNAL_PATH_RESET_TEMP_RESET));
+
+ ao_mpu6000_reg_write(MPU6000_SIGNAL_PATH_RESET,
+ (0 << MPU6000_SIGNAL_PATH_RESET_GYRO_RESET) |
+ (0 << MPU6000_SIGNAL_PATH_RESET_ACCEL_RESET) |
+ (0 << MPU6000_SIGNAL_PATH_RESET_TEMP_RESET));
+ /* Select clocks, disable sleep */
+ ao_mpu6000_reg_write(MPU6000_PWR_MGMT_1,
+ (0 << MPU6000_PWR_MGMT_1_DEVICE_RESET) |
+ (0 << MPU6000_PWR_MGMT_1_SLEEP) |
+ (0 << MPU6000_PWR_MGMT_1_CYCLE) |
+ (0 << MPU6000_PWR_MGMT_1_TEMP_DIS) |
+ (MPU6000_PWR_MGMT_1_CLKSEL_PLL_X_AXIS << MPU6000_PWR_MGMT_1_CLKSEL));
+
+ /* Set sample rate divider to sample at full speed
+ ao_mpu6000_reg_write(MPU6000_SMPRT_DIV, 0);
+
+ /* Disable filtering */
+ ao_mpu6000_reg_write(MPU6000_CONFIG,
+ (MPU6000_CONFIG_EXT_SYNC_SET_DISABLED << MPU6000_CONFIG_EXT_SYNC_SET) |
+ (MPU6000_CONFIG_DLPF_CFG_260_256 << MPU6000_CONFIG_DLPF_CFG));
+
+ /* Configure accelerometer to +/-16G in self-test mode */
+ ao_mpu6000_reg_write(MPU6000_ACCEL_CONFIG,
+ (1 << MPU600_ACCEL_CONFIG_XA_ST) |
+ (1 << MPU600_ACCEL_CONFIG_YA_ST) |
+ (1 << MPU600_ACCEL_CONFIG_ZA_ST) |
+ (MPU600_ACCEL_CONFIG_AFS_SEL_16G << MPU600_ACCEL_CONFIG_AFS_SEL));
+
+ /* Configure gyro to +/- 2000°/s in self-test mode */
+ ao_mpu6000_reg_write(MPU6000_GYRO_CONFIG,
+ (1 << MPU600_GYRO_CONFIG_XG_ST) |
+ (1 << MPU600_GYRO_CONFIG_YG_ST) |
+ (1 << MPU600_GYRO_CONFIG_ZG_ST) |
+ (MPU600_GYRO_CONFIG_FS_SEL_2000 << MPU600_GYRO_CONFIG_FS_SEL));
+
+ ao_delay(AO_MS_TO_TICKS(200));
+ ao_mpu6000_sample(&test_mode);
+
+ /* Configure accelerometer to +/-16G */
+ ao_mpu6000_reg_write(MPU6000_ACCEL_CONFIG,
+ (0 << MPU600_ACCEL_CONFIG_XA_ST) |
+ (0 << MPU600_ACCEL_CONFIG_YA_ST) |
+ (0 << MPU600_ACCEL_CONFIG_ZA_ST) |
+ (MPU600_ACCEL_CONFIG_AFS_SEL_16G << MPU600_ACCEL_CONFIG_AFS_SEL));
+
+ /* Configure gyro to +/- 2000°/s */
+ ao_mpu6000_reg_write(MPU6000_GYRO_CONFIG,
+ (0 << MPU600_GYRO_CONFIG_XG_ST) |
+ (0 << MPU600_GYRO_CONFIG_YG_ST) |
+ (0 << MPU600_GYRO_CONFIG_ZG_ST) |
+ (MPU600_GYRO_CONFIG_FS_SEL_2000 << MPU600_GYRO_CONFIG_FS_SEL));
+
+ ao_delay(AO_MS_TO_TICKS(10));
+ ao_mpu6000_sample(&normal_mode);
+
+ ao_mpu6000_accel_check(normal_mode.accel_x, test_mode.accel_x, "x");
+ ao_mpu6000_accel_check(normal_mode.accel_y, test_mode.accel_y, "y");
+ ao_mpu6000_accel_check(normal_mode.accel_z, test_mode.accel_z, "z");
+
+ ao_mpu6000_gyro_check(normal_mode.gyro_x, test_mode.gyro_x, "x");
+ ao_mpu6000_gyro_check(normal_mode.gyro_y, test_mode.gyro_y, "y");
+ ao_mpu6000_gyro_check(normal_mode.gyro_z, test_mode.gyro_z, "z");
+
+ /* Filter to about 100Hz, which also sets the gyro rate to 1000Hz */
+ ao_mpu6000_reg_write(MPU6000_CONFIG,
+ (MPU6000_CONFIG_EXT_SYNC_SET_DISABLED << MPU6000_CONFIG_EXT_SYNC_SET) |
+ (MPU6000_CONFIG_DLPF_CFG_94_98 << MPU6000_CONFIG_DLPF_CFG));
+
+ /* Set sample rate divider to sample at 200Hz (v = gyro/rate - 1) */
+ ao_mpu6000_reg_write(MPU6000_SMPRT_DIV,
+ 1000 / 200 - 1);
+
+ ao_delay(AO_MS_TO_TICKS(100));
ao_mpu6000_configured = 1;
}
+
static void
ao_mpu6000_show(void)
{
- uint8_t addr;
- uint8_t data[14];
- uint8_t i;
-
- ao_mpu6000_read(MPU6000_WHO_AM_I, data, 1);
- printf ("mpu6000 WHO_AM_I: %02x\n", data[0]);
-#if 0
- ao_mpu6000_read(MPU6000_ACCEL_XOUT_H, data, 14);
- for (i = 0; i < 14; i++)
- printf ("reg %02x: %02x\n", i + MPU6000_ACCEL_XOUT_H, data[i]);
-#endif
+ struct ao_mpu6000_sample sample;
+
+ ao_mpu6000_setup();
+ ao_mpu6000_sample(&sample);
+ printf ("Accel: %7d %7d %7d Gyro: %7d %7d %7d\n",
+ ao_mpu6000_accel(sample.accel_x),
+ ao_mpu6000_accel(sample.accel_y),
+ ao_mpu6000_accel(sample.accel_z),
+ ao_mpu6000_gyro(sample.gyro_x),
+ ao_mpu6000_gyro(sample.gyro_y),
+ ao_mpu6000_gyro(sample.gyro_z));
}
static const struct ao_cmds ao_mpu6000_cmds[] = {
#define MPU6000_ADDR_WRITE 0xd0
#define MPU6000_ADDR_READ 0xd1
-#define MPU6000_ACCEL_XOUT_H 0x3b
+#define MPU6000_SMPRT_DIV 0x19
+
+#define MPU6000_CONFIG 0x1a
+
+#define MPU6000_CONFIG_EXT_SYNC_SET 3
+#define MPU6000_CONFIG_EXT_SYNC_SET_DISABLED 0
+#define MPU6000_CONFIG_EXT_SYNC_SET_TEMP_OUT_L 1
+#define MPU6000_CONFIG_EXT_SYNC_SET_GYRO_XOUT_L 2
+#define MPU6000_CONFIG_EXT_SYNC_SET_GYRO_YOUT_L 3
+#define MPU6000_CONFIG_EXT_SYNC_SET_GYRO_ZOUT_L 4
+#define MPU6000_CONFIG_EXT_SYNC_SET_ACCEL_XOUT_L 5
+#define MPU6000_CONFIG_EXT_SYNC_SET_ACCEL_YOUT_L 6
+#define MPU6000_CONFIG_EXT_SYNC_SET_ACCEL_ZOUT_L 7
+#define MPU6000_CONFIG_EXT_SYNC_SET_MASK 7
+
+#define MPU6000_CONFIG_DLPF_CFG 0
+#define MPU6000_CONFIG_DLPF_CFG_260_256 0
+#define MPU6000_CONFIG_DLPF_CFG_184_188 1
+#define MPU6000_CONFIG_DLPF_CFG_94_98 2
+#define MPU6000_CONFIG_DLPF_CFG_44_42 3
+#define MPU6000_CONFIG_DLPF_CFG_21_20 4
+#define MPU6000_CONFIG_DLPF_CFG_10_10 5
+#define MPU6000_CONFIG_DLPF_CFG_5_5 6
+#define MPU6000_CONFIG_DLPF_CFG_MASK 7
+
+#define MPU6000_GYRO_CONFIG 0x1b
+# define MPU600_GYRO_CONFIG_XG_ST 7
+# define MPU600_GYRO_CONFIG_YG_ST 6
+# define MPU600_GYRO_CONFIG_ZG_ST 5
+# define MPU600_GYRO_CONFIG_FS_SEL 3
+# define MPU600_GYRO_CONFIG_FS_SEL_250 0
+# define MPU600_GYRO_CONFIG_FS_SEL_500 1
+# define MPU600_GYRO_CONFIG_FS_SEL_1000 2
+# define MPU600_GYRO_CONFIG_FS_SEL_2000 3
+# define MPU600_GYRO_CONFIG_FS_SEL_MASK 3
+
+#define MPU6000_ACCEL_CONFIG 0x1c
+# define MPU600_ACCEL_CONFIG_XA_ST 7
+# define MPU600_ACCEL_CONFIG_YA_ST 6
+# define MPU600_ACCEL_CONFIG_ZA_ST 5
+# define MPU600_ACCEL_CONFIG_AFS_SEL 3
+# define MPU600_ACCEL_CONFIG_AFS_SEL_2G 0
+# define MPU600_ACCEL_CONFIG_AFS_SEL_4G 1
+# define MPU600_ACCEL_CONFIG_AFS_SEL_8G 2
+# define MPU600_ACCEL_CONFIG_AFS_SEL_16G 3
+# define MPU600_ACCEL_CONFIG_AFS_SEL_MASK 3
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF 0
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_RESET 0
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_5Hz 1
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_2_5Hz 2
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_1_25Hz 3
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_0_63Hz 4
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_HOLD 7
+# define MPU600_ACCEL_CONFIG_ACCEL_HPF_MASK 7
+
+#define MPU6000_INT_ENABLE 0x38
+#define MPU6000_INT_ENABLE_FF_EN 7
+#define MPU6000_INT_ENABLE_MOT_EN 6
+#define MPU6000_INT_ENABLE_ZMOT_EN 5
+#define MPU6000_INT_ENABLE_FIFO_OFLOW_EN 4
+#define MPU6000_INT_ENABLE_I2C_MST_INT_EN 3
+#define MPU6000_INT_ENABLE_DATA_RDY_EN 0
+
+#define MPU6000_INT_STATUS 0x3a
+#define MPU6000_INT_STATUS_FF_EN 7
+#define MPU6000_INT_STATUS_MOT_EN 6
+#define MPU6000_INT_STATUS_ZMOT_EN 5
+#define MPU6000_INT_STATUS_FIFO_OFLOW_EN 4
+#define MPU6000_INT_STATUS_I2C_MST_INT_EN 3
+#define MPU6000_INT_STATUS_DATA_RDY_EN 0
+
+#define MPU6000_ACCEL_XOUT_H 0x3b
+#define MPU6000_ACCEL_XOUT_L 0x3c
+#define MPU6000_ACCEL_YOUT_H 0x3d
+#define MPU6000_ACCEL_YOUT_L 0x3e
+#define MPU6000_ACCEL_ZOUT_H 0x3f
+#define MPU6000_ACCEL_ZOUT_L 0x40
+#define MPU6000_TEMP_H 0x41
+#define MPU6000_TEMP_L 0x42
+#define MPU6000_GYRO_XOUT_H 0x43
+#define MPU6000_GYRO_XOUT_L 0x44
+#define MPU6000_GYRO_YOUT_H 0x45
+#define MPU6000_GYRO_YOUT_L 0x46
+#define MPU6000_GYRO_ZOUT_H 0x47
+#define MPU6000_GYRO_ZOUT_L 0x48
+
+#define MPU6000_SIGNAL_PATH_RESET 0x68
+#define MPU6000_SIGNAL_PATH_RESET_GYRO_RESET 2
+#define MPU6000_SIGNAL_PATH_RESET_ACCEL_RESET 1
+#define MPU6000_SIGNAL_PATH_RESET_TEMP_RESET 0
+
+#define MPU6000_USER_CONTROL 0x6a
+#define MPU6000_USER_CONTROL_FIFO_EN 6
+#define MPU6000_USER_CONTROL_I2C_MST_EN 5
+#define MPU6000_USER_CONTROL_I2C_IF_DIS 4
+#define MPU6000_USER_CONTROL_FIFO_RESET 2
+#define MPU6000_USER_CONTROL_I2C_MST_RESET 1
+#define MPU6000_USER_CONTROL_SIG_COND_RESET 0
+
+#define MPU6000_PWR_MGMT_1 0x6b
+#define MPU6000_PWR_MGMT_1_DEVICE_RESET 7
+#define MPU6000_PWR_MGMT_1_SLEEP 6
+#define MPU6000_PWR_MGMT_1_CYCLE 5
+#define MPU6000_PWR_MGMT_1_TEMP_DIS 3
+#define MPU6000_PWR_MGMT_1_CLKSEL 0
+#define MPU6000_PWR_MGMT_1_CLKSEL_INTERNAL 0
+#define MPU6000_PWR_MGMT_1_CLKSEL_PLL_X_AXIS 1
+#define MPU6000_PWR_MGMT_1_CLKSEL_PLL_Y_AXIS 2
+#define MPU6000_PWR_MGMT_1_CLKSEL_PLL_Z_AXIS 3
+#define MPU6000_PWR_MGMT_1_CLKSEL_PLL_EXTERNAL_32K 4
+#define MPU6000_PWR_MGMT_1_CLKSEL_PLL_EXTERNAL_19M 5
+#define MPU6000_PWR_MGMT_1_CLKSEL_STOP 7
+#define MPU6000_PWR_MGMT_1_CLKSEL_MASK 7
+
+#define MPU6000_PWR_MGMT_2 0x6c
+
#define MPU6000_WHO_AM_I 0x75
+/* Self test acceleration is approximately 0.5g */
+#define MPU6000_ST_ACCEL(full_scale) (32767 / ((full_scale) * 2))
+
+/* Self test gyro is approximately 50°/s */
+#define MPU6000_ST_GYRO(full_scale) ((int16_t) (((int32_t) 32767 * (int32_t) 50) / (full_scale)))
+
+struct ao_mpu6000_sample {
+ int16_t accel_x;
+ int16_t accel_y;
+ int16_t accel_z;
+ int16_t temp;
+ int16_t gyro_x;
+ int16_t gyro_y;
+ int16_t gyro_z;
+};
+
void
ao_mpu6000_init(void);