UART Problem

[lgiordano2]

Posted on June 06, 2006 at 10:27

UART Problem

[lgiordano2]

Posted on June 06, 2006 at 10:27

Hi, I am having some trouble with UARTs. It happens not very often, but it happens.

I am using the 4 UARTs. In the middle of a data transfer through UART3, (half duplex, which sends some data, waits ACK, sends more data, and so on..) it suddenly hangs my application. By making some debug with JTAG, I noticed that UART0 enters in the interrupt routine countinously (as if some interrupt bit is always set), but I dont know why. These are the values of some registers I got from UART0:

CR: 0x05A9

IER: 0x0140

SR: 0x0006

My communication module (the one who handles the 4 UARTs) is using interrupts and FIFOs. It just makes some buffering of data.

This code is the ISR:

Code:

static void CommISRHandler(commbuffer_t *pBuffer, UART_TypeDef *UARTx)

{

uint16_t FlagStatus;

uint16_t nError;

FlagStatus = UART_FlagStatus(UARTx) & UARTx->IER;

/* Check any TX Interrupt */

if (FlagStatus & (UART_TxEmpty | UART_TxHalfEmpty)) {

do {

/* Is there any data to send? */

if (0 == pBuffer->BufferTxCtr) {

/* No, so turn off TX interrupts */

UART_ItConfig(UARTx, UART_TxEmpty | UART_TxHalfEmpty, DISABLE);

break;

}

/* Put new data */

UARTx->TxBUFR = CommGetCharISR(pBuffer, &nError);

/* Repeat until UART is full */

} while (UART_FlagStatus(UARTx) & UART_TxFull);

}

/* Check any RX Interrupt */

if (FlagStatus & (UART_RxHalfFull | UART_TimeOutNotEmpty)) {

do {

/* Add Data to Buffer */

CommPutCharISR(pBuffer, UARTx->RxBUFR);

/* UART_RxBufFull in fact means UART_RxBufNotEmpty */

/* So, repeat until no data is present */

} while (UART_FlagStatus(UARTx) & UART_RxBufFull);

}

}

The ISR has two parameters:

commbuffer_t *pBuffer -> points to the corresponding buffer structure

UART_TypeDef *UARTx -> points to corresponding UART

My 4 UART Interrupt handlers only call this routine, for instance:

Code:

void Comm0ISR(void)

{

CommISRHandler(Buffers[0], UART0);

return;

}

Any suggestion?

Regards,