Posted on May 17, 2011 at 13:58I think you shouldn't have the STOP in the middle of your routine and I'm not sure about the ACK disable.
Your code looks similar to some I use to read another I2C device with device address, register number and byte read(s) - which seems to work. Does it help you?
John F.
#define DeviceAddress 0xCE
void DeviceReadBuffer(uint8_t* pBuffer, uint8_t NumByteToRead)
{
/*!< While the bus is busy */
while(I2C_GetFlagStatus(I2C1, I2C_FLAG_BUSY))
{
}
/*!< Send START condition */
I2C_GenerateSTART(I2C1, ENABLE);
/*!< Test on EV5 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))
{
}
/*!< Send EEPROM address for write */
I2C_Send7bitAddress(I2C1, LTC4151Address, I2C_Direction_Transmitter);
/*!< Test on EV6 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_TRANSMITTER_MODE_SELECTED))
{
}
//send the reg select COMMAND byte
I2C_SendData(I2C1, 0);
/*!< Test on EV8 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_TRANSMITTED))
{
}
//send START condition a second time
I2C_GenerateSTART(I2C1, ENABLE);
/*!< Test on EV5 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_MODE_SELECT))
{
}
/*!< Send EEPROM address for read */
I2C_Send7bitAddress(I2C1, LTC4151Address, I2C_Direction_Receiver);
/*!< Test on EV6 and clear it */
while(!I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_RECEIVER_MODE_SELECTED))
{
}
/*!< While there is data to be read */
while(NumByteToRead)
{
if(NumByteToRead == 1)
{
/*!< Disable Acknowledgement */
I2C_AcknowledgeConfig(I2C1, DISABLE);
/*!< Send STOP Condition */
I2C_GenerateSTOP(I2C1, ENABLE);
}
/*!< Test on EV7 and clear it */
if(I2C_CheckEvent(I2C1, I2C_EVENT_MASTER_BYTE_RECEIVED))
{
/*!< Read a byte from the EEPROM */
*pBuffer = I2C_ReceiveData(I2C1);
/*!< Point to the next location where the byte read will be saved */
pBuffer++;
/*!< Decrement the read bytes counter */
NumByteToRead--;
}
}
/*!< Enable Acknowledgement to be ready for another reception */
I2C_AcknowledgeConfig(I2C1, ENABLE);
}
