Posted on February 08, 2015 at 17:14
Hi,
I have STM32VLDISCOVERY that needs to read temperature from MLX90614 over I2C bus.
Here is part of code I am using to read registers and it never pass line I am using pull up resistor of 10k. Does someone know what may be a problem?
uint8_t I2C_address;
uint32_t I2C_speed;
GPIO_InitTypeDef GPIO_InitStructure;
I2C_InitTypeDef I2C_InitStructure;
I2C_address = 0x5A<<1;
//
I2C_speed = 100000;
// 1000Hz
/* I2C1 clock enable */
RCC_APB1PeriphClockCmd(RCC_APB1Periph_I2C1, ENABLE);
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOB, ENABLE);
/* I2C1 SDA and SCL configuration */
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6 | GPIO_Pin_7;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_OD;
GPIO_Init(GPIOB, &GPIO_InitStructure);
//SCL is pin06 and SDA is pin 07 for I2C1
/* I2C1 configuration */
I2C_InitStructure.I2C_Mode = I2C_Mode_SMBusHost;
I2C_InitStructure.I2C_DutyCycle = I2C_DutyCycle_2;
I2C_InitStructure.I2C_OwnAddress1 = 0x00;
I2C_InitStructure.I2C_Ack = I2C_Ack_Enable;
I2C_InitStructure.I2C_AcknowledgedAddress = I2C_AcknowledgedAddress_7bit;
I2C_InitStructure.I2C_ClockSpeed = I2C_speed ;
I2C_Init(I2C1, &I2C_InitStructure);
I2C_Cmd(I2C1,ENABLE);
I2C_AcknowledgeConfig(I2C1, ENABLE);
/* Test on BUSY Flag */
while
(I2C_GetFlagStatus(I2C1,I2C_FLAG_BUSY));
/* Enable the I2C peripheral */
/*======================================================*/
I2C_GenerateSTART(I2C1, ENABLE);
/* Test on start flag */
while
(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT));
/* Send device address for write */
I2C_Send7bitAddress(I2C1, I2C_address, I2C_Direction_Transmitter);
/* Test on master Flag */
while
(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED));
/* Send the device's internal address to write to */
I2C_SendData(I2C1,0x07);
/* Test on TXE FLag (data sent) */
while
(!I2C_GetFlagStatus(I2C1,I2C_FLAG_TXE));
