/* * Copyright © 2012 Keith Packard * * 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; version 2 of the License. * * 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. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include #include #include static uint8_t ao_mpu6000_wake; static uint8_t ao_mpu6000_configured; static void ao_mpu6000_write(uint8_t addr, uint8_t *data, uint8_t len) { 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_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(d, 2, AO_MPU6000_I2C_INDEX, TRUE); ao_i2c_put(AO_MPU6000_I2C_INDEX); } static void 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_send(&addr, 1, AO_MPU6000_I2C_INDEX, FALSE); ao_i2c_start(AO_MPU6000_I2C_INDEX, MPU6000_ADDR_READ); ao_i2c_recv(data, len, AO_MPU6000_I2C_INDEX, TRUE); 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)); #if __BYTE_ORDER == __LITTLE_ENDIAN /* byte swap */ while (i--) { uint16_t t = *d; *d++ = (t >> 8) | (t << 8); } #endif } #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) { return 1; } if (diff > MPU6000_ST_ACCEL(16) * 2) { return 1; } return 0; } 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) { return 1; } if (diff > MPU6000_ST_GYRO(2000) * 2) { return 1; } return 0; } static void ao_mpu6000_setup(void) { struct ao_mpu6000_sample normal_mode, test_mode; int errors =0; if (ao_mpu6000_configured) return; /* Reset the whole chip */ ao_mpu6000_reg_write(MPU6000_PWR_MGMT_1, (1 << MPU6000_PWR_MGMT_1_DEVICE_RESET)); /* Wait for it to reset. If we talk too quickly, it appears to get confused */ ao_delay(AO_MS_TO_TICKS(100)); /* 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); errors += ao_mpu6000_accel_check(normal_mode.accel_x, test_mode.accel_x, "x"); errors += ao_mpu6000_accel_check(normal_mode.accel_y, test_mode.accel_y, "y"); errors += ao_mpu6000_accel_check(normal_mode.accel_z, test_mode.accel_z, "z"); errors += ao_mpu6000_gyro_check(normal_mode.gyro_x, test_mode.gyro_x, "x"); errors += ao_mpu6000_gyro_check(normal_mode.gyro_y, test_mode.gyro_y, "y"); errors += ao_mpu6000_gyro_check(normal_mode.gyro_z, test_mode.gyro_z, "z"); if (errors) ao_panic(AO_PANIC_SELF_TEST_MPU6000); /* 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; } struct ao_mpu6000_sample ao_mpu6000_current; static void ao_mpu6000(void) { ao_mpu6000_setup(); for (;;) { ao_mpu6000_sample(&ao_mpu6000_current); ao_arch_critical( AO_DATA_PRESENT(AO_DATA_MPU6000); AO_DATA_WAIT(); ); } } static struct ao_task ao_mpu6000_task; static void ao_mpu6000_show(void) { struct ao_data sample; ao_data_get(&sample); printf ("Accel: %7d %7d %7d Gyro: %7d %7d %7d\n", sample.mpu6000.accel_x, sample.mpu6000.accel_y, sample.mpu6000.accel_z, sample.mpu6000.gyro_x, sample.mpu6000.gyro_y, sample.mpu6000.gyro_z); } static const struct ao_cmds ao_mpu6000_cmds[] = { { ao_mpu6000_show, "I\0Show MPU6000 status" }, { 0, NULL } }; void ao_mpu6000_init(void) { ao_mpu6000_configured = 0; ao_add_task(&ao_mpu6000_task, ao_mpu6000, "mpu6000"); ao_cmd_register(&ao_mpu6000_cmds[0]); }