On Thu, 27 Aug 1998 09:57:49 -0700 Ralph Landry writes: > Although I might >have the key under my nose. I was looking at the data sheet for the >16C65A, it has a built in async UART. From what I can tell, and I'll >have to experiment with it some. I only need to select the baud rate >generator, set a couple of registers and by virtual of writing the >output byte to a register it will bit shift and send it out. Yes, the built in UART hardware will do most of the work for you. You may need to change the crystal to one that makes the baud rate work out with BRGH = 0. The chip has a bug when the BRGH bit is set, though it affects the receiver so it may not be a problem for you. On the other hand, it wouldn't be hard to use a standard software "bit-bang" output in this case since the PIC doesn't need to do anything else while outputting data. The advantage to that is that you can move down to a less expensive PIC that doesn't have a UART. A 65 is probably overkill for your application. receiver does not work properly with the BRGH bit set, so > I understand that I'll still have to use a TTL to 232 >converter. >I have a bunch of LT1081 from Linear. Any experience with using >some low power devices that would meet my application? See if the 1081 has a power down control pin. Or use the PIC to switch power to the converter chip off when it's not in use. That may be as simple as connecting the power supply pin to an output of the PIC, which can supply 20 mA. A low power chip isn't really needed, since it will be active so infrequently. _____________________________________________________________________ You don't need to buy Internet access to use free Internet e-mail. Get completely free e-mail from Juno at http://www.juno.com Or call Juno at (800) 654-JUNO [654-5866]