SC18IM704 UART

[Fritz23]

Hello, I have a problem with the chip SC18IM704. The response to the Read from GPIO port command often overlaps with the sent message see attached screenshots. Is this the reply from the previous message? The message to query the IO is sent every 20 ms.

[tomas3456]

Hello, I'm having the same problem.  I can't read any internal register as SC18IM704 starts responding before the message from the master is terminated with the 'P' character. I tried with 9600 and 115200 kbps, and it looked the same.

The identification message is working correctly, the "OK" message is transmitted after startup as well. Writing the internal register was obviously ok as well since I managed to switch the baudrate. 

I tried to power SC18IM704 down, for checking the message from master and it was ok.

Can you please help me?

Thank you.

Tomas

line without SC18IM704.JPG

line with SC18IM704 damaged message.JPG

read version ok.JPG

   

[guoweisun]

What about the result for reducing the read speed? Still has same issue?