diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/fsm/i2c.c | 71 |
1 files changed, 47 insertions, 24 deletions
diff --git a/src/fsm/i2c.c b/src/fsm/i2c.c index 8215ec7..b1b5e3a 100644 --- a/src/fsm/i2c.c +++ b/src/fsm/i2c.c @@ -96,15 +96,32 @@ void i2c_init() i2c_init_done = 1; } +static int i2c_check_event(uint32_t event) +{ + const TickType_t i2c_timeout = 1000ul / portTICK_PERIOD_MS; + const TickType_t time_start = xTaskGetTickCount(); + + while (!I2C_CheckEvent(I2Cx, event)) { + const TickType_t time_now = xTaskGetTickCount(); + + if (time_now - time_start > i2c_timeout) { + return 0; + } + } + + return 1; +} static int i2c_start(uint8_t device, uint8_t direction) { I2C_GenerateSTART(I2Cx, ENABLE); - // wait for I2C1 EV5 --> Slave has acknowledged start condition - while (!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_MODE_SELECT)); + // wait for bus free + if (!i2c_check_event(I2C_EVENT_MASTER_MODE_SELECT)) { + I2C_GenerateSTART(I2Cx, DISABLE); + return 0; + } - // Send slave Address for write I2C_Send7bitAddress(I2Cx, device << 1, direction); /* wait for I2C1 EV6, check if @@ -123,7 +140,9 @@ static int i2c_start(uint8_t device, uint8_t direction) trigger_fault(FAULT_SOURCE_I2C); } - while (!I2C_CheckEvent(I2Cx, event)); + if (!i2c_check_event(event)) { + return 0; + } return 1; } @@ -133,9 +152,7 @@ static int i2c_send(uint8_t data) I2C_SendData(I2Cx, data); // wait for I2C1 EV8_2 --> byte has been transmitted - while (!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED)); - - return 1; + return i2c_check_event(I2C_EVENT_MASTER_BYTE_TRANSMITTED); } int i2c_write(uint8_t device, const uint8_t *txbuf, int len) @@ -155,9 +172,10 @@ int i2c_write(uint8_t device, const uint8_t *txbuf, int len) break; } } + + I2C_GenerateSTOP(I2Cx, ENABLE); + success = i2c_check_event(I2C_EVENT_MASTER_BYTE_TRANSMITTED); } - I2C_GenerateSTOP(I2Cx, ENABLE); - while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED)); return success; } @@ -168,26 +186,31 @@ static int i2c_read_nobuscheck(uint8_t device, uint8_t *rxbuf, int len) trigger_fault(FAULT_SOURCE_I2C); } - i2c_start(device, I2C_Direction_Receiver); - for (int i = 0; i < len; i++) { - if (i == len-1) { - I2C_AcknowledgeConfig(I2Cx, DISABLE); - } - else { - I2C_AcknowledgeConfig(I2Cx, ENABLE); - } + if (i2c_start(device, I2C_Direction_Receiver)) { + for (int i = 0; i < len; i++) { + if (i == len-1) { + I2C_AcknowledgeConfig(I2Cx, DISABLE); + } + else { + I2C_AcknowledgeConfig(I2Cx, ENABLE); + } - // wait until one byte has been received - while( !I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED) ); + // wait until one byte has been received, possibly timout + if (!i2c_check_event(I2C_EVENT_MASTER_BYTE_RECEIVED)) { + I2C_GenerateSTOP(I2Cx, ENABLE); + return 0; + } - if (i == len-1) { - I2C_GenerateSTOP(I2Cx, ENABLE); - } + if (i == len-1) { + I2C_GenerateSTOP(I2Cx, ENABLE); + } - rxbuf[i] = I2C_ReceiveData(I2Cx); + rxbuf[i] = I2C_ReceiveData(I2Cx); + } + return len; } - return len; + return 0; } int i2c_read(uint8_t device, uint8_t *rxbuf, int len) |