At 10:15 AM 5/13/2005, kenasw@btinternet.com wrote: >----- Original Message ----- >From: "Dave VanHorn" >To: "Microcontroller discussion list - Public." ; >"Microcontroller discussion list - Public." >Sent: Friday, May 13, 2005 2:45 PM >Subject: Re: [PIC] RS232, USART, and COM > > > > > > > > > >I do understand now, i.e. RS232 is usefull to extend the u(s)art >interface > > >over a long distance, i.e. 1 or 2 or 3 meters, but when our signals >travel > > >only a few centimeters on a pcb, we do not need rs232 and in fact rs232 > > >will simply be a hinderance. > > > > Exactly. > >Well, another difference (?) is also that RS232 has other signals apart from >TX and RX which if I understand correctly belong to the UART, i.e. >TX and RX come from the UART standard, the others (CTS,RTS,DSR....) >are only RS232 signals, i.e. they do not exist in UART interfaces. They are routinely implemented by general purpose I/O bits, but earlier uarts like the SIO-0 did implement a lot of those signals, and they even would handle the handshaking for you. http://www.z80.info/z80sio.htm -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist