BL1800 Port D serial communication issue.

Hi,

I am using BL1800 and trying to send and receive serial data on port D. Although I have been successful in sending serial data through Port D, I can't receive any sort of data on it. I have painstakingly verified that the bytes coming back from the external device is making back all the way to the processor, but I simply can't capture the bytes in my code. Every time I read, it returns with all zeros. Also, from looking at the schematic for the processor, I found out that PC0 is for sending and PC1 is for receiving serial data on Port D (correct me if I am wrong).

This is how I am writing:

Jr485Tx();

delay(10);

serDwrite(&PortAdxout[0],6);

while(BitRdPortI(SDSR,SS_TFULL_BIT) != 0);
while(BitRdPortI(SDSR,SS_TPRG_BIT) == 1);

This is how I am reading:

t=MS_TIMER;
Jr485Rx();
delay(10);

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

myret=serDread(&PortAdxin[0],5,100);

So, what am I doing wrong? The funny thing is all this was working before and last couple of days I was making some changes in the code. From then on, it never worked even when I compiled and uploaded the original working code.

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Just as a first pass, this is my old code from 2004 that worked:

Jr485Init() // needed first and once only.

CommWrite() first, followed by comm read snippet at the end.

nodebug BOOL CommWrite1810(char *Command, int Count)
{
BOOL CWrite;

serDwrFlush(); // Clear Rx and Tx data buffers
serDrdFlush();
Jr485Tx(); // Enable transmitter

CWrite = serDwrite(Command, Count);

while(serDwrUsed() > 0); // Wait for bytes to be output
MyDelay(m_MyDelay);

while(serDrdUsed() > 0)
serDgetc(); // Flush echoed bytes

Jr485Rx(); // Disable transmitter

return(CWrite == Count);
}

// Read extract:
for(Limit = MS_TIMER + TimeOut; MS_TIMER < Limit; )
{
n = serDread(RBuf, ExpectedLength, TimeOut);
if(n > 0)
return n;
}
--- In r..., "TN" wrote:
>
> Hi,
>
> I am using BL1800 and trying to send and receive serial data on port D. Although I have been successful in sending serial data through Port D, I can't receive any sort of data on it. I have painstakingly verified that the bytes coming back from the external device is making back all the way to the processor, but I simply can't capture the bytes in my code. Every time I read, it returns with all zeros. Also, from looking at the schematic for the processor, I found out that PC0 is for sending and PC1 is for receiving serial data on Port D (correct me if I am wrong).
>
> This is how I am writing:
>
> Jr485Tx();
>
> delay(10);
>
> serDwrite(&PortAdxout[0],6);
>
> while(BitRdPortI(SDSR,SS_TFULL_BIT) != 0);
> while(BitRdPortI(SDSR,SS_TPRG_BIT) == 1);
>
> This is how I am reading:
>
> t=MS_TIMER;
> Jr485Rx();
> delay(10);
>
> while(serDpeek()==-1)
> {
> if (MS_TIMER>(t+100))
> break;
> }
>
> myret=serDread(&PortAdxin[0],5,100);
>
> So, what am I doing wrong? The funny thing is all this was working before and last couple of days I was making some changes in the code. From then on, it never worked even when I compiled and uploaded the original working code.
>

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