diff --git a/drivers/include/srf02.h b/drivers/include/srf02.h index 82f3506e0c..275ac48637 100644 --- a/drivers/include/srf02.h +++ b/drivers/include/srf02.h @@ -34,7 +34,7 @@ extern "C" { /** * @brief Default I2C address of SRF02 sensors */ -#define SRF02_DEFAULT_ADDR 112 +#define SRF02_DEFAULT_ADDR (0xe0) /** * @brief Device descriptor for SRF02 sensors @@ -85,6 +85,14 @@ int srf02_init(srf02_t *dev, i2c_t i2c, uint8_t addr); */ uint16_t srf02_get_distance(srf02_t *dev, srf02_mode_t mode); +/** + * @brief Program the given device with a new bus address + * + * @param[in] dev device to program + * @param[in] new_addr new address to program the given device to + */ +void srf02_set_addr(srf02_t *dev, uint8_t new_addr); + #ifdef __cplusplus } #endif diff --git a/drivers/srf02/srf02.c b/drivers/srf02/srf02.c index 953cdd7cf7..d357851e0f 100644 --- a/drivers/srf02/srf02.c +++ b/drivers/srf02/srf02.c @@ -28,7 +28,7 @@ #include "srf02.h" #include "periph/i2c.h" -#define ENABLE_DEBUG (0) +#define ENABLE_DEBUG (0) #include "debug.h" /** @@ -52,10 +52,20 @@ #define REG_AUTO_LOW (0x05) /** @} */ +/** + * @brief Some additional SRF02 commands + * @{ + */ +#define CMD_ADDR_SEQ1 (0xa0) +#define CMD_ADDR_SEQ2 (0xaa) +#define CMD_ADDR_SEQ3 (0xa5) +/** @} */ + + int srf02_init(srf02_t *dev, i2c_t i2c, uint8_t addr) { dev->i2c = i2c; - dev->addr = addr; + dev->addr = (addr >> 1); /* internally we right align the 7-bit addr */ char rev; /* Acquire exclusive access to the bus. */ @@ -66,7 +76,7 @@ int srf02_init(srf02_t *dev, i2c_t i2c, uint8_t addr) return -1; } /* try to read the software revision (read the CMD reg) from the device */ - i2c_read_reg(i2c, addr, REG_CMD, &rev); + i2c_read_reg(i2c, dev->addr, REG_CMD, &rev); if (rev == 0 || rev == 255) { DEBUG("[srf02] error reading the devices software revision\n"); return -1; @@ -102,3 +112,21 @@ uint16_t srf02_get_distance(srf02_t *dev, srf02_mode_t mode) /* compile result - TODO: fix for different host byte order other than LE */ return ((((uint16_t)res[0]) << 8) | (res[1] & 0xff)); } + +void srf02_set_addr(srf02_t *dev, uint8_t new_addr) +{ + /* get access to the bus */ + i2c_acquire(dev->i2c); + + DEBUG("[srf02] reprogramming device address to 0x%02x\n", (int)new_addr); + + /* write the new address, for this we need to follow a certain sequence */ + i2c_write_reg(dev->i2c, dev->addr, REG_CMD, CMD_ADDR_SEQ1); + i2c_write_reg(dev->i2c, dev->addr, REG_CMD, CMD_ADDR_SEQ2); + i2c_write_reg(dev->i2c, dev->addr, REG_CMD, CMD_ADDR_SEQ3); + i2c_write_reg(dev->i2c, dev->addr, REG_CMD, new_addr); + dev->addr = (new_addr >> 1); + + /* release the bus */ + i2c_release(dev->i2c); +}