UART or USART, which to choose

[Karbos]

I have been working on RS-232 communication lately and I am currently at the point of if I should use UART or USART. USART can operate at faster speeds, but UART has more support. Therefore I am quite confused as what to choose. Perhaps any of you could clear up my problem.

 

[Nigel Goodwin]

Well RS232 uses a UART - so your problem is solved.

I don't see as there's any more support for either?, both are simple, one uses two wires, one uses just one (both plus ground of course).

What are you trying to do?.

 

[philba]

A USART is a superset of a UART. If you are asking should you use Synchronous or Asynchronous serial I/O, that's different. Both UART and USART support Async which is what is used by PCs for serial I/O. What specific UART are you looking at and what speeds doesn't it support.

 

[Karbos]

To be more specific the PIC I shall be using is a 18F4620. It has the TX and RX pins, but for TX it states:
"Asynchronous serial transmit data (EUSART module)"
and for RX:
"Asynchronous serial receive data input (EUSART module)"

Am I able to still use UART?

 

[blueroomelectronics]

It's an enhanced UART. But it's still a uart.

 

[Karbos]

Ok, thanks. I shall use the 18F4620 in UART mode, with both the TX and RX lines. If I am not mistaken, that is all that is needed to use in UART mode correct?

 

[blueroomelectronics]

Yep that's it. Look for USART calculator on these forums or my web site. It'll do the register calculations for you.

 

[Karbos]

I have built the ST232CN board with the 9 pin connector. I will finish the board over the course of this weekend.

 

[cGr]

I didn't understand a thing.If we need Synchronous comunication,which one we will use?

 

[Nigel Goodwin]

I didn't understand a thing.If we need Synchronous comunication,which one we will use?

The USART in a PIC can be configured to do either, easy as pie.