Hi Team, Seeking for some assistance for a customer.
Wrapper to communicate on a i2c bus. this one looks like this:
int8_t user_i2c_read(uint8_t reg_addr, uint8_t *reg_data, uint32_t len, void *intf_ptr)
{
int8_t rslt = 0; /* Return 0 for Success, non-zero for failure */
uint8_t i = 0;
/*
* The parameter intf_ptr can be used as a variable to store the I2C address of the device
*/
/*
* Data on the bus should be like
* |------------+---------------------|
* | I2C action | Data |
* |------------+---------------------|
* | Start | - |
* | Write | (reg_addr) |
* | Stop | - |
* | Start | - |
* | Read | (reg_data[0]) |
* | Read | (....) |
* | Read | (reg_data[len - 1]) |
* | Stop | - |
* |------------+---------------------|
*/
I2CMasterSlaveAddrSet(I2C0_BASE, *(uint8_t *)intf_ptr, false);
I2CMasterDataPut(I2C0_BASE, reg_addr);
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_SINGLE_SEND);
while (I2CMasterBusy(I2C0_BASE)) {
}
I2CMasterSlaveAddrSet(I2C0_BASE, *(uint8_t *)intf_ptr, false);
if ( len == 1){
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_SINGLE_RECEIVE);
while (I2CMasterBusy(I2C0_BASE)) ;
reg_data[0] = I2CMasterDataGet(I2C0_BASE);
}else {
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_BURST_RECEIVE_START);
while (I2CMasterBusy(I2C0_BASE)) ;
reg_data[0] = I2CMasterDataGet(I2C0_BASE);
for(i = 0 ; i < len -2 ; i++){
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_BURST_RECEIVE_CONT);
while (I2CMasterBusy(I2C0_BASE)) ;
reg_data[i+1] = I2CMasterDataGet(I2C0_BASE);
}
I2CMasterControl(I2C0_BASE,I2C_MASTER_CMD_BURST_RECEIVE_FINISH);
while (I2CMasterBusy(I2C0_BASE)) ;
reg_data[i+1] = I2CMasterDataGet(I2C0_BASE);
return rslt;
}
On the scope to see what is happening on the bus is see the following :
The Address is correct and the Data send is also okay but i am wondering why the second slot is not a read slot. The master sends tow times the same. I nee the first slot like we see and the second slot must be a read slot on the same Adress. if you need some more informations pleas let me know. thank you for your help.
Thank you in advance for your help.
-Mark
