8-bit serial to parallel convertor verilog with synchronization

[arishsu]

Hi
I need to write a code for rs-232 serial data to parallel convertor.I can write Serial to parallel code, but the problem is i have to write a code such that i have to ensure synchronization with the sending device. How can I add synchronization? Also I didn't find any pin in RS-232 for synchronization. Is any pin in rs232 which can be used for synch?

 

[ads-ee]

There is no pin for synchronization. The RS-232 serial protocol has a start and stop bit, logic 0 and 1 respectively. An idle channel will have a logic 1. So if the channel goes from idle to active, 0 will be the first thing you see. If you pick up the channel in the middle of transmission you'll end up having to find the pattern of 10 repeating every 10 bits (8-bit data). I actually don't think anyone does that type of synchronization. From observation of devices that used RS-232 to receive data, I always remember seeing garbage if you hooked it up in the middle of a burst of data. I think most devices need a pause before achieving synchornization.
https://www.commfront.com/RS232_Protocol_Analyzer_Monitor/RS232_Analyzer_Monitor_Tester_Tutorial.htm

Regards

 

[arishsu]

Hi ads-ee
In serial transmission suppose source and destination uses different clocks and we don't know source's frequency, then destination may not receive all data correctly, right? How can we find a solution to this?

 

[ads-ee]

Designs I've seen oversample the input data using an oversampling clock along with a baud clock at the expected frequency.

Regards