Hello,
I am developing custom driver for TWIM. I am facing a problem with DNACK and ANACK which hangs my application. SCL and SDA lines are monitored through Saleale logic analyzer and an oscilloscope. The problem occures when no ACK appears after address byte (high level).
To simplify the problem I will describe the polling configuration. A code snipped is placed below:
i2c.TXD.MAXCNT = length + 1;
i2c.ADDRESS = (deviceAddress >> 1);
i2c.TXD.PTR = reinterpret_cast<uint32_t>(buffer);
eventClear(Event::LastTX);
eventClear(Event::Error);
taskTrigger(Task::StartTx);
do {
if (eventCheck(Event::LastTX)) {
eventClear(Event::LastTX);
taskTrigger(Task::Stop);
}
if (eventCheck(Event::Error)) {
eventClear(Event::Error);
taskTrigger(Task::Stop);
return getError();
}
if (eventCheck(Event::Stopped)) {
eventClear(Event::Stopped);
break;
}
if (getError() != I2C::Error::NoError) {
taskTrigger(Task::Stop);
return AcknowledgeFailure;
}
} while (1);
return NoError;
After ANACK occures no events are reported, therefore getError conditional statement was added. getError function reads the i2c.ERRORSRC register and cleans it. Error is reported, but the next transmission on I2C does not starts. What's more - no event and no error is reported, above loop after next calling does not ends.
I will be grateful for any help.
