Posted on May 17, 2011 at 09:40Hello,
in the following code I use the I2C0 in IRQ mode.
I have to read the temperature from a LM75
The device is adressed 0x91 (readmode) followed with 2 bytes.
I analyzed the scl and sck line with the oscilloscope and the signal seem
correct.
The Temp sensor send a data but I always receive FF
The port configuration reflect the following configuration:
// ****************************************************************
// GPIO input register setting
// ****************************************************************
#define GPIOIN2 0x41
// ****************************************************************
// GPIO output register setting
// ****************************************************************
#define GPIOOUT2 0x8A5A
// ****************************************************************
// GPIO type register setting
// ****************************************************************
#define GPIOTYPE2 0x3
--------
the code
--------
void main()
{
DeviceInit();
/* I2C0 Configuration */
I2C_Cmd(I2C0, ENABLE);
SCU_APBPeriphClockConfig(__I2C0,ENABLE);
I2C_DeInit(I2C0);
SCU_AHBPeriphClockConfig(__VIC, ENABLE);
VIC_DeInit();
/* I2C0 Configuration */
I2C_Struct.I2C_GeneralCall = I2C_GeneralCall_Disable;
I2C_Struct.I2C_Ack = I2C_Ack_Enable;
I2C_Struct.I2C_CLKSpeed = 20000;
I2C_Init(I2C0, &I2C_Struct);
/* VIC Configuration */
VIC_Config(I2C0_ITLine,VIC_IRQ , 1);
VIC_ITCmd(I2C0_ITLine, ENABLE);
I2C_ITConfig(I2C0, ENABLE);
/*--------------------------------------------------*/
/* Reception Phase----------------------------------*/
/*--------------------------------------------------*/
/*reset counters*/
Tx_Idx = Rx_Idx = 0;
Direction = I2C_MODE_RECEIVER;
while(1)
{
Rx_Idx = 0;
I2C_GenerateStart(I2C0, ENABLE);
while (Rx_Idx < BUFFER_SIZE);
/* Check if the transmitted data is read correctly */
Delay(100000);
}
while(1)
{
}
}
void I2C0_IRQHandler(void)
{
u16 event1 = I2C0->SR1;
u16 event2 = I2C0->SR2;
if ( event1 & 0x01 )
{
// case I2C_EVENT_MASTER_MODE_SELECT: // EV5
I2C_Send7bitAddress(I2C0, I2C_SLAVE_ADDRESS7, Direction);
}
else if ( event2 & 0x20 )
{
// case I2C_EVENT_MASTER_MODE_SELECTED: // EV6
// Clear EV6 by set again the PE bit
I2C0->CR |= 0x20;
if (Direction == I2C_MODE_TRANSMITTER)
I2C_SendData(I2C0, I2C0_Buffer_Tx[Tx_Idx++]);//EV8 just after EV6
}
else if ( (event1 & 0x08) && (Direction == I2C_MODE_TRANSMITTER) )
{
// case I2C_EVENT_MASTER_BYTE_TRANSMITTED: // EV8
if ( Tx_Idx == BUFFER_SIZE )
{
I2C_GenerateSTOP (I2C0, ENABLE);
Tx_Idx++;
}
else
{
I2C_SendData(I2C0, I2C0_Buffer_Tx[Tx_Idx]);
Tx_Idx++;
}
}
else if ( event1 & 0x08 )
{
// case I2C_EVENT_MASTER_BYTE_RECEIVED: // EV7
I2C0_Buffer_Rx[Rx_Idx++] = I2C_ReceiveData(I2C0);
if ( Rx_Idx == BUFFER_SIZE-2 )
{
I2C_AcknowledgeConfig (I2C0, DISABLE);
}
if ( Rx_Idx == BUFFER_SIZE-1 )
{
/* Send STOP Condition */
I2C_GenerateSTOP(I2C0, ENABLE);
}
}
}
Any suggestion is appreciated!!
