STR730 UART TimeOut

[philip1]

Posted on June 28, 2006 at 07:36

STR730 UART TimeOut

[philip1]

Posted on May 19, 2006 at 08:07

Hi All,

I am using the STR730FZ2T6 device with UARTs running at 500kbaud (over RS485) and using 8-bit data plus wakeup mode to address one of a set of receiving devices, followed by 9-bit data.

I am trying to use the UART receive timeout so that I can leave the UART alone until the incoming data message is complete and stored in the receive FIFO.

First interrupt received performs the following:

if(wUART_ReceiveData == (0x100 | MyAddress))

{

UART3->CR = (UART3->CR & 0xFFF8) | UART_Mode_9D;

UART3->IER &= ~UART_Flag_RxBufFull;

UART3->IER |= (UART_IT_TimeOutIdle | UART_IT_TimeOutNotEmpty);

}

next interrupt is:

if((wUART_Status & UART_Flag_TimeOutNotEmpty) != 0)

{

while((UART3->SR & UART_Flag_RxBufFull) != 0)

{

wUART_ReceiveData = UART3->RxBUFR;

}

UART3->CR = (UART3->CR & 0xFFF8) | UART_Mode_8D_W;

UART3->IER &= ~(UART_IT_TimeOutIdle | UART_IT_TimeOutNotEmpty);

UART3->IER |= UART_Flag_RxBufFull;

}

This works but the time between the two interrupts (which should be determined by the value I load into the TimeOut register, UART3->TOR) is always the same (~290uS), regardless of what I write into TOR.

Also it says on the data sheet that writing to the TOR should cause the countdown timer to reload and therefore hold-off the interrupt, this is not happening!

Has anyone had any success with the TimeOut feature?

It would seem that my program cannot write to the TOR register! have a missed soething that need to be done to ''open the access'' to this TOR register?

grateful for any help or suggestions

PhilipJ :p

cadac electronics

[philip1]

Posted on June 28, 2006 at 07:36

for anyone who is interested in using this feature, I found out what the problem was. There is a mistake in the C library file 73x_map.h

In the structure defining the UART registers it should be:

typedef struct

{

vu16 BR; /*BaudRate register*/

u16 EMPTY1;

vu16 TxBUFR; /*TxBuffer Register*/

u16 EMPTY2;

vuc16 RxBUFR; /*RxBuffer Register*/

u16 EMPTY3;

vu16 CR; /*Control Register*/

u16 EMPTY4;

vu16 IER; /*IntEnable Register*/

u16 EMPTY5;

vuc16 SR; /*Status Register*/

u16 EMPTY6;

u16 EMPTY7;

u16 EMPTY8;

vu16 TOR; /*Timeout Register*/

u16 EMPTY9;

vu16 TxRSTR; /*TxReset register*/

u16 EMPTY10;

vu16 RxRSTR; /*RxReset register*/

u16 EMPTY11;

} UART_TypeDef;

Note the two extra EMPTY's just before the TOR register!!!

Hope this saves someone the days of trouble I had trying to get things to work properly!!

PhilipJ