diff options
Diffstat (limited to 'src/lpc176x/i2c.c')
| -rw-r--r-- | src/lpc176x/i2c.c | 35 |
1 files changed, 34 insertions, 1 deletions
diff --git a/src/lpc176x/i2c.c b/src/lpc176x/i2c.c index 4d8dc361..7ed631af 100644 --- a/src/lpc176x/i2c.c +++ b/src/lpc176x/i2c.c @@ -100,6 +100,20 @@ i2c_send_byte(LPC_I2C_TypeDef *i2c, uint8_t b, uint32_t timeout) return i2c->I2STAT; } +static uint8_t +i2c_read_byte(LPC_I2C_TypeDef *i2c, uint32_t timeout, uint8_t remaining) +{ + if (remaining == 0) + i2c->I2CONCLR = IF_ACK | IF_IRQ; + else { + i2c->I2CONSET = IF_ACK; + i2c->I2CONCLR = IF_IRQ; + } + i2c_wait(i2c, IF_IRQ, timeout); + uint8_t b = i2c->I2DAT; + return b; +} + static void i2c_stop(LPC_I2C_TypeDef *i2c, uint32_t timeout) { @@ -125,5 +139,24 @@ void i2c_read(struct i2c_config config, uint8_t reg_len, uint8_t *reg , uint8_t read_len, uint8_t *read) { - shutdown("i2c_read not supported on lpc176x"); + LPC_I2C_TypeDef *i2c = config.i2c; + uint32_t timeout = timer_read_time() + timer_from_us(5000); + uint8_t addr = config.addr | 0x01; + + if (reg_len != 0) { + // write the register + i2c_start(i2c, timeout); + i2c_send_byte(i2c, config.addr, timeout); + while(reg_len--) + i2c_send_byte(i2c, *reg++, timeout); + i2c_stop(i2c, timeout); + } + // start/re-start and read data + i2c_start(i2c, timeout); + i2c_send_byte(i2c, addr, timeout); + while(read_len--) { + *read = i2c_read_byte(i2c, timeout, read_len); + read++; + } + i2c_stop(i2c, timeout); } |