diff options
Diffstat (limited to 'src/fsm/i2c.c')
| -rw-r--r-- | src/fsm/i2c.c | 189 |
1 files changed, 150 insertions, 39 deletions
diff --git a/src/fsm/i2c.c b/src/fsm/i2c.c index da109fc..8215ec7 100644 --- a/src/fsm/i2c.c +++ b/src/fsm/i2c.c @@ -23,20 +23,56 @@ */ #include "i2c.h" +#include "common.h" #include "stm32f4xx_conf.h" #include "stm32f4xx_i2c.h" #include "stm32f4xx.h" +#include "FreeRTOS.h" +#include "FreeRTOSConfig.h" +#include "task.h" +#include "semphr.h" static int i2c_init_done = 0; +static int i2c_error = 0; static I2C_TypeDef* const I2Cx = I2C1; +static SemaphoreHandle_t i2c_semaphore; + +static void i2c_device_init(void) +{ + // configure I2C1 + I2C_InitTypeDef I2C_InitStruct; + I2C_InitStruct.I2C_ClockSpeed = 100000; //Hz + I2C_InitStruct.I2C_Mode = I2C_Mode_I2C; + I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2; // 50% duty cycle + I2C_InitStruct.I2C_OwnAddress1 = 0x00; // not relevant in master mode + + // disable acknowledge when reading (can be changed later on) + I2C_InitStruct.I2C_Ack = I2C_Ack_Disable; + + I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; + I2C_Init(I2C1, &I2C_InitStruct); + + // enable I2C1 + I2C_Cmd(I2C1, ENABLE); +} + void i2c_init() { if (i2c_init_done == 1) { return; } + i2c_semaphore = xSemaphoreCreateBinary(); + + if ( i2c_semaphore == NULL ) { + trigger_fault(FAULT_SOURCE_I2C); + } + else { + xSemaphoreGive(i2c_semaphore); + } + RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE); RCC_APB1PeriphClockCmd(RCC_AHB1Periph_GPIOB, ENABLE); @@ -56,32 +92,17 @@ void i2c_init() RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, ENABLE); RCC_APB1PeriphResetCmd(RCC_APB1Periph_I2C1, DISABLE); - // configure I2C1 - I2C_InitTypeDef I2C_InitStruct; - I2C_InitStruct.I2C_ClockSpeed = 100000; //Hz - I2C_InitStruct.I2C_Mode = I2C_Mode_I2C; - I2C_InitStruct.I2C_DutyCycle = I2C_DutyCycle_2; // 50% duty cycle - I2C_InitStruct.I2C_OwnAddress1 = 0x00; // not relevant in master mode - - // disable acknowledge when reading (can be changed later on) - I2C_InitStruct.I2C_Ack = I2C_Ack_Disable; - - I2C_InitStruct.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit; - I2C_Init(I2C1, &I2C_InitStruct); - - // enable I2C1 - I2C_Cmd(I2C1, ENABLE); - + i2c_device_init(); i2c_init_done = 1; } -static void i2c_start(uint8_t device, uint8_t direction) +static int i2c_start(uint8_t device, uint8_t direction) { - while(I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY)); I2C_GenerateSTART(I2Cx, ENABLE); + // wait for I2C1 EV5 --> Slave has acknowledged start condition - while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_MODE_SELECT)); + while (!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_MODE_SELECT)); // Send slave Address for write I2C_Send7bitAddress(I2Cx, device << 1, direction); @@ -91,47 +112,137 @@ static void i2c_start(uint8_t device, uint8_t direction) * Master receiver mode, depending on the transmission * direction */ - if(direction == I2C_Direction_Transmitter) { - while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED)); + uint32_t event = 0; + if (direction == I2C_Direction_Transmitter) { + event = I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED; } - else if(direction == I2C_Direction_Receiver) { - while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED)); + else if (direction == I2C_Direction_Receiver) { + event = I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED; } + else { + trigger_fault(FAULT_SOURCE_I2C); + } + + while (!I2C_CheckEvent(I2Cx, event)); + + return 1; } -static void i2c_send(uint8_t data) { +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)); + while (!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED)); + + return 1; } -void i2c_write(uint8_t device, const uint8_t *txbuf, int len) { - i2c_start(device, I2C_Direction_Transmitter); - for (int i = 0; i < len; i++) { - i2c_send(txbuf[i]); +int i2c_write(uint8_t device, const uint8_t *txbuf, int len) +{ + if (i2c_init_done == 0) { + trigger_fault(FAULT_SOURCE_I2C); + } + + while (I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY)); + + int success = 0; + + if (i2c_start(device, I2C_Direction_Transmitter)) { + for (int i = 0; i < len; i++) { + success = i2c_send(txbuf[i]); + if (!success) { + break; + } + } } I2C_GenerateSTOP(I2Cx, ENABLE); + while(!I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_TRANSMITTED)); + + return success; } -int i2c_read(uint8_t device, uint8_t *rxbuf, int len) +static int i2c_read_nobuscheck(uint8_t device, uint8_t *rxbuf, int len) { + if (i2c_init_done == 0) { + 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, ENABLE); - // wait until one byte has been received - while( !I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED) ); - rxbuf[i] = I2C_ReceiveData(I2Cx); + if (i == len-1) { + I2C_AcknowledgeConfig(I2Cx, DISABLE); } else { - I2C_AcknowledgeConfig(I2Cx, DISABLE); + I2C_AcknowledgeConfig(I2Cx, ENABLE); + } + + // wait until one byte has been received + while( !I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED) ); + + if (i == len-1) { I2C_GenerateSTOP(I2Cx, ENABLE); - // wait until one byte has been received - while( !I2C_CheckEvent(I2Cx, I2C_EVENT_MASTER_BYTE_RECEIVED) ); - rxbuf[i] = I2C_ReceiveData(I2Cx); } + + rxbuf[i] = I2C_ReceiveData(I2Cx); } return len; } +int i2c_read(uint8_t device, uint8_t *rxbuf, int len) +{ + while (I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY)); + + return i2c_read_nobuscheck(device, rxbuf, len); +} + +int i2c_read_from(uint8_t device, uint8_t address, uint8_t *rxbuf, int len) +{ + if (i2c_init_done == 0) { + trigger_fault(FAULT_SOURCE_I2C); + } + + while (I2C_GetFlagStatus(I2Cx, I2C_FLAG_BUSY)); + + int success = i2c_start(device, I2C_Direction_Transmitter); + if (success) { + success = i2c_send(address); + } + // Don't do a STOP + + if (success) { + success = i2c_read_nobuscheck(device, rxbuf, len); + } + + return success; +} + + + +void i2c_transaction_start() +{ + if (i2c_init_done == 0) { + trigger_fault(FAULT_SOURCE_I2C); + } + xSemaphoreTake(i2c_semaphore, portMAX_DELAY); +} + +void i2c_transaction_end() +{ + if (i2c_init_done == 0) { + trigger_fault(FAULT_SOURCE_I2C); + } + + if ( i2c_error ) { + I2C_SoftwareResetCmd(I2Cx, ENABLE); + I2C_SoftwareResetCmd(I2Cx, DISABLE); + + i2c_device_init(); + + i2c_error = 0; + } + + xSemaphoreGive(i2c_semaphore); +} + |