diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/stm32/stm32f0_i2c.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/src/stm32/stm32f0_i2c.c b/src/stm32/stm32f0_i2c.c index da632c35..381fe8b4 100644 --- a/src/stm32/stm32f0_i2c.c +++ b/src/stm32/stm32f0_i2c.c @@ -224,16 +224,18 @@ i2c_read(struct i2c_config config, uint8_t reg_len, uint8_t *reg uint8_t *write_orig = reg; uint8_t *read_orig = read; - // Send start, address, reg - i2c->CR2 = (I2C_CR2_START | config.addr | - (reg_len << I2C_CR2_NBYTES_Pos)); - while (reg_len--) { - ret = i2c_wait(i2c, I2C_ISR_TXIS, timeout); - if (ret != I2C_BUS_SUCCESS) - goto abrt; - i2c->TXDR = *reg++; + if (reg_len) { + // Send start, address, reg + i2c->CR2 = (I2C_CR2_START | config.addr | + (reg_len << I2C_CR2_NBYTES_Pos)); + while (reg_len--) { + ret = i2c_wait(i2c, I2C_ISR_TXIS, timeout); + if (ret != I2C_BUS_SUCCESS) + goto abrt; + i2c->TXDR = *reg++; + } + i2c_wait(i2c, I2C_ISR_TC, timeout); } - i2c_wait(i2c, I2C_ISR_TC, timeout); // send restart, read data i2c->CR2 = (I2C_CR2_START | I2C_CR2_RD_WRN | config.addr | |