Newsgroups: comp.sys.mac.hardware
Path: utzoo!utgpu!nishri
From: nishri@gpu.utcs.utoronto.ca (Alex Nishri)
Subject: Re: MAC II serial port problems
Message-ID: <1990Feb15.200733.26380@gpu.utcs.utoronto.ca>
Organization: UTCS Public Access
References: <23884@ipl.jpl.nasa.gov> <210@brain.UUCP>
Date: Thu, 15 Feb 90 20:07:33 GMT

In article <210@brain.UUCP> root@brain.UUCP (Chuck Shotton) writes:
>tcg060@ipl.jpl.nasa.gov (Tom Greer) writes:
>
>>HELP!
>>For the fourth time in my Mac II's life, the modem port has died.  The 
>>first two times, it "healed" itself.  Once, right in front of the Mac 
>>repair person.  The next time, my Mac was taken away for a week and then
>>returned with the comment that nothing was wrong... except for my hard disk
>>which crashed when the repair folks dropped it.  
>
>>Has anyone seen this?  Know a simple fix?
>
>Every time this has happened to me, UNPLUGGING the Mac II after zapping PRAM and
>shutting down has worked. Let the thing sit for about 10 minutes unplugged, and
>then power it up. Works for me.

I think I have the same problem.

We have a Mac IIcx where the modem port doesn't work.  (The printer port works
fine both for Appletalk as well as when it is used as a serial port from an
application like Red Ryder.)  The symptoms are:

Application	Dialog

uw 4.2		he RAM serial driver couldn't be opened.  The ROM driver will
		be used; however flow  (SIC)

Red Ryder 10.3	Gadzooks!  I cannot open the serial port requested.  It may
		already be in use by another application, desk accessory,
		or Appletalk.

MacWorkStation 3.0 An error occurred which suggests the port is not configured
		correctly.  Please check and try again.  Error: -28

Settime		none.  (It just hangs.)

Kermit 0.9(40)	Can't open RAM serial driver; using the ROM driver without
		flow control. <ok>
		(second dialog after saying ok to first) Fatal error: macinit
		could not OpenDriver .AIn: -98

Of these, MacWorkStation and Kermit are the only useful ones in that they do
give a return code to follow up.  MacWorkStation reports -28 and that means
"couldn't rd/wr/ctl/sts cause driver not opened"; this suggests that
MacWorkStation ignored the result code from an OpenDriver() call, which is what
it should have reported.  Kermit reports -98 which means "driver open error.
Parameter RAM not configured for this connection."

To confirm that KERMIT is dead on I ran the follow C program:

	main() {
		int aout , ain;
		aout = -7 ;
		ain = -6 ;
		printf("out %d\n",OpenDriver(".AOut",&aout));
		printf("in %d\n",OpenDriver(".AIn",&ain));
	}

The result code from both OpenDriver() calls is -98.  I checked out two more
Mac IIs.  The first, a Mac IIx, gave the result code of zero from my C program
and KERMIT worked fine on it.  The second machine I tried, a brand new
Mac IIci, failed with the -98 code, and KERMIT didn't work on it.

I tried zapping PRAM (holding down the option, command and shift key as I open
the control panel.)  When running Multifinder I get a bing as the dialog comes
up to confirm PRAM zap, and a bing after I click ok.  With finder I only get
the second bing.  In both cases my feeling is that PRAM was not zapped.  I
tried this on other machines and I have no evidence that zapping PRAM works.
Does anyone know if it does?  (Somebody said that there was a DA which zaps
PRAM, but I can't find it.  Anyone know about this?)

I did talk to our Apple authorized hardware repair person.  He is very
knowledgable about Macintosh software and hardware.  When he talked to Apple
about this, the answer was to swap the motherboard.  However, if there is a
solution to this problem which doesn't involve swapping boards I would prefer
it.  (And yes I tried zapping PRAM and unplugging the machine, and it did
not work for me.)