------------ Category 21, Topic 13 Message 1 Mon Feb 04, 1991 J.MCGEE2 at 21:56 CST I'm trying to interface a C-64 to a Broadcast Character Generator. (Through the 232 port via Aprotek interface). The CG requires "1 start bit, 8 data bits, 1 stop bit, no parity" I don't see anything in my books that says anything about using a start bit on either 64 or 128. I know I can program it 8N1, but can the 64 handle the start bit, and if so how? ------------ Category 21, Topic 13 Message 2 Tue Feb 05, 1991 C128.JBEE at 19:48 EST I know you can set some terminals to one or two stop bits. Maybe they are talking about the second stop bit? Beats me. ------------ Category 21, Topic 13 Message 3 Thu Feb 07, 1991 E.DURKIN1 [Montana Kid] at 16:57 MST Does it work without a start bit? I have _no_ idea what a start bit is,but if it ain't broke - why fix it?! ;) -==- ------------ Category 21, Topic 13 Message 4 Thu Feb 07, 1991 J.MCGEE2 at 19:37 CST Well I don't know, I have yet to write the program to control it, but I ain't gonna write it if I know it won't work beforehand. I've asked this question of others and haven't had much luck yet. Hopefully... ------------ Category 21, Topic 13 Message 5 Thu Feb 07, 1991 VOYAGER-1 [Gary V] at 21:45 EST As far as I know, a start bit is a standard feature of RS-232 communications. It is automatically taken care of by the UART chip ( or in the case of the 64 & 128 - the operating system software ). A start bit is required for the receiver to get ready for a data byte. With no data being transmitted, the line is held low. If the first bit of data was a binary zero ( also a low voltage ), the receiver would have no idea that the beginning of a data byte has begun. The start bit sets the line high for one bit cycle to tell the receiver that the next 8 bit cycles are data. So unless you are rewriting the RS-232 operating system routines, you should be fine. ------------ Category 21, Topic 13 Message 6 Fri Feb 08, 1991 J.MCGEE2 at 19:43 CST Thanks, Gary. I didn't know that, but now I do. Start bit is not even referenced at all in either the 64 or 128 Programmers Ref. Guide, so it had me puzzled. I'll plow ahead & see what happens. ------------ Category 21, Topic 13 Message 7 Sun Feb 10, 1991 R.RANDALL5 [Zeroy] at 04:11 EST One start bit is normal with all asychronous communications. There is always one start bit and I don't know of any scheme that uses anything else than one start bit. Therefore, most communications setups neglect to mention it. ------------ Category 21, Topic 13 Message 8 Sun Feb 10, 1991 C128.JBEE at 21:56 EST Thanks Gary! That was a pretty good answer. I learned something new today :D ------------ REPly to topic, QUIt reading STArt new topic, #,#-# read prior PERmanently ignore this topic or to continue ?