-=> Quoting Rodrigo Cesar Banhara to Leonard Erickson <=-

 -=> Quoting Leonard Erickson to Roy J. Tellason <=-
 
 LE> The 2000 has some nice features, such as using USARTs instead of UARTs
 LE> on the COM ports. And 640x400 graphics (2 color or 16 color depending

 RCB> mm... interesting, but what the difference between these UARTs?

 UART = Universal Asyschonrous Receiver/Transmitter
USART = Universal Synchronous/Asynchronous Receiver Transmitter

A UART can't handle a true synchronous link. A USART can. 

Most PC folks don't know much about synch links, *because* synch cards
for PCs are *expensive* and not well supported. 

One of the simpler aspects of the difference is that a synchronous link
doesn't *have* start bits and stop bits. Thus 8-bit, no parity data
moves 1.25 (10/8) times as fast over a synchronous link. 

You do pay for this. Anytime a new byte isn't ready to be sent in time,
you have to add a "dummy" byte to maintain synch. And usually, you
dedicate one byte value to this, and have to use some sort of escape
char to actually send that value. Even so, synch is still faster than async.

synch links tend to be *inherently* bi-directional also. 

The main reason I'm interested in synch links is because I've got a
pair of CSU/DSU units that can do 56k if connected to a sync interface,
and only 19.2k if hooked to an async one. 

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