how do you timeout waiting for data back from the JackRabbit?

Rabbit Rabbit Software
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#1

How do you wait for serial data coming back from the processor?

What flags do you look for or wait on?

I tried all the followings conditions for timeout and none of them seem to work.

while(serDpeek()==-1)

while(BitRdPortI(SDSR, SS_RRDY_BIT) == 0)

while(serDrdUsed()<7)

Here is a complete while loop for timeout.

t = MS_TIMER;

while ( serDpeek() == -1)
{
if (MS_TIMER>(t+100)
break;
}

serDpeek always returns as though there is data to read when in fact no data has been received. With SDSR, SS_RRDY_BIT flag, it always indicates that port D is ready for reading. As for as serDrdUsed function goes, I have no idea what it is doing.

#2

Take a look at samples\serial\EchoChr.c. This program waits on serDgetc() to return success (0)

Here is the function description:

SYNTAX: int serDgetc(void);

DESCRIPTION: Get next available character from serial port D read buffer.
This function is non-reentrant.

PARAMETER1: None

RETURN VALUE: If successful, the next character in the low byte and 0 in
the high byte of the integer result;
otherwise, the integer -1 which indicates either an empty
or a locked receive buffer.

1 Like
#3

Thank you so much.