SOMCYC@NUSVM.BITNET (Chiang Yao Chye) (07/09/90)
Can anyone who knows the answer please enlighten me: Why is it that on the IIGS, you cannot have the modem port and AppleTalk both active at the same time? Thanks.
toddpw@tybalt.caltech.edu (Todd P. Whitesel) (07/10/90)
SOMCYC@NUSVM.BITNET (Chiang Yao Chye) writes: >Why is it that on the IIGS, you cannot have the modem port and AppleTalk both >active at the same time? First of all, you ARE plugging Appletalk into the printer port AND setting slot 1 to "Your Card" ?? If you aren't then Appletalk doesn't know whether to use the printer or the modem port because it thinks both are being used for serial. Second, and this is what you probably meant, they can't both be active at the same time because every time a long Appletalk packet comes in, the appletalk driver has to pull the whole thing from the serial port, and if more than three characters come in from the modem then the modem port will lose them, because the serial chip can remember the last three characters received but no more than that. Since the longest Appletalk packet can be upwards of 10 9600 baud character times, this can cause some major character loss from the modem. The real solution is to rewrite the SCC Manager so that characters from both ports are received properly (I believe this is how the Mac's serial ports are handled) -- I am pretty sure this is possible but it would have to do some assembly experiments first. Todd Whitesel toddpw @ tybalt.caltech.edu
gwyn@smoke.BRL.MIL (Doug Gwyn) (07/10/90)
In article <9007091651.AA03831@apple.com> SOMCYC@NUSVM.BITNET (Chiang Yao Chye) writes: >Why is it that on the IIGS, you cannot have the modem port and AppleTalk both >active at the same time? AppleTalk needs to use one of the two halves of the 8530 SCC chip.
dlyons@Apple.COM (David A. Lyons) (07/14/90)
In article <9007091651.AA03831@apple.com> SOMCYC@NUSVM.BITNET (Chiang Yao Chye) writes: > >Can anyone who knows the answer please enlighten me: > >Why is it that on the IIGS, you cannot have the modem port and AppleTalk both >active at the same time? > >Thanks. What? You can. Just plug LocalTalk into the Printer port. What happens for you? I don't usually use my GS here at work for telcom work, but I *have* tried it, and I was on a LocalTalk network, and I don't even remember losing any characters. (It's possible there was little LocalTalk activity in my zone at the time, since many of the machines in this zone are Macintoshes running EtherTalk instead of LocalTalk.) (Why can't you have LocalTalk, the modem port, *and* the printer port ALL at the same time? Because LocalTalk plugs into one of the serial ports.) -- David A. Lyons, Apple Computer, Inc. | DAL Systems Apple II Developer Technical Support | P.O. Box 875 America Online: Dave Lyons | Cupertino, CA 95015-0875 GEnie: D.LYONS2 or DAVE.LYONS CompuServe: 72177,3233 Internet/BITNET: dlyons@apple.com UUCP: ...!ames!apple!dlyons My opinions are my own, not Apple's.
whitewolf@gnh-starport.cts.com (Tae Song) (07/16/90)
>Can anyone who knows the answer please enlighten me: > >Why is it that on the IIGS, you cannot have the modem port and AppleTalk both >active at the same time? You can. There are only two serial ports on the GS, you have to decide either to have Printer and AppleTalk or Modem and AppleTalk or Modem and Printer. You just can't have all three at the same time. If you want all three you could get FingerPrint GSi (or something) card which fits into a slot, but does not disable any of built-in ports or devices.