IIGS: "Visit Monitor" 03 Same as Released Version



Is there a difference between the Apple IIGS (ROM 03) I own, and other
Apple IIGS systems with ROM version 03? My 03 is one of the first few
hundred that were accidentally assembled with "Memory Peeker" and "Visit
Monitor" stuck in the Classic Desk Accessories menu.

Anyway, I've documented a list of things that seem to be wrong with my ROM
03 Apple IIGS. Could you try out the things on the list with your ROM 03
(one without "Memory Peeker" and "Visit Monitor" in the CDA menu), and let
me know if any of those things happen on your Apple IIGS.

The System Monitor
------------------
After entering Monitor with a "CALL-151" command or accessing it through
"Visit Monitor/CDA", the system will freeze after entering the "LIST"
command. Pressing any key after this causes a continuous scroll of
inverse text, while the Error bell rings non-stop. Strangely enough,
pressing certain keys will display different graphic modes while this is
happening, replacing the scrolling text, but with the error bell still
ringing, and no way to stop it.

Applesoft BASIC
---------------
When trying to run any program written in Applesoft BASIC that launches
GS-specific programs (i.e., doing calls to Apple IIGS ROMs or hardware),
the program will not run and gives this error message:

?SYNTAX ERROR IN 65182

All programs give the same error message. After this error message occurs
from trying to load an Applesoft BASIC program, the GS/OS operating system
won't run. Trying to load any disk that uses GS/OS to boot up will
crash after the "Welcome to the Apple IIGS" message appears and gives the
following error message:

Error Loading Apple IIGS.OS File. Error=$002E

After this you must turn the computer off for 30 seconds or more before
you can load GS/OS without getting the same error message.

MDIdeas Card
------------
When plugged into my ROM 03 Apple IIGS, the Stereo/Digitizer card from
MDIdeas, does not function properly. Any sound that's recorded with the
card is played back with an echo, and is noisy and scratchy (incompatible
with either card or software). The card and software are not at fault,
because they work perfectly on my other Apple IIGS, which is a ROM 01.

Software
--------
Many software applications will not run on my Apple IIGS with the 03 ROMs,
while they apparently run on other 03 ROM-d systems. (This includes
public-domain and commercial software titles.)

RAM Disk
--------
With 2.125MB in my Apple IIGS, there's a maximum RAM disk size of 1,920K.
The system will not auto-format a RAM disk larger than 1,888K in size.
Selecting 1,920K from Control Panel won't auto-format.

* Each time you reset the computer to auto-format a RAM disk, the system
freezes for 5 or more seconds.

* When a RAM disk is created, the system will erase the entire RAM disk
after using Open-Apple Reset command a couple of times. (It seems to
change the setting in the Control Panel to "Resize after reset: YES",
thereby changing the setting by itself.)

Disk Access Slows Down
----------------------
When loading up some GS-specific programs that use ProDOS 8 or ProDOS 16 as
a launcher, the computer seems to have trouble loading ProDOS, and then
trouble loading the main program system file. The program will take two to
three times longer to start up than it will on a ROM 01-GS or other ROM
03-GS systems. It slows down so much that it appears the disk is damaged
or corrupted. Some examples of programs that have this problem are
"Diversi-Tune" and "Tunnel of Armageddon".

Most of these problems can be avoided. The ROMs (early and late) are
identical. Some systems went out configured improperly. Anyway, I'll take
them one at a time.

System Monitor
--------------
"LIST" is not a Monitor command. To list the contents of memory locations,
you only need to type "l" or "L". When the monitor sees "LIST" it scrolls
20 lines of location contents and then sets the display to inverse. The
monitor queues commands typed as a string; the second command in the string
is "i"; the command for inverse. "S" and "T" are not Monitor commands and
seem to confuse the system. Typing "l", a carriage return, "i" and a
carriage return works fine. You should read the "Apple IIGS Firmware
Reference" for a complete description of the Monitor and its commands.

Applesoft BASIC
---------------
Without an exact description of the steps required to create the problem
described, we can only speculate as to the cause of the problem.

It sounds as if you are trying to run a ProDOS-16 application from
ProDOS-8. Whatever the case, some memory locations are being stomped on,
seriously scrambling memory, because the system thinks a disk has been
switched. If this continues to be a problem, let us know exactly what you
are doing to cause this crash, and we'll dig into it.

MDIdeas Card
------------
The MDIdeas card was developed for the original Apple IIGS. The company is
now out of business and has therefore not upgraded the product to work with
the new ROMs. The card (or perhaps the accompanying software) is not
compatible with the new version of the ROMs. Applied Engineering offers a
comparable product that is compatible with the new ROMs.

Software
--------
We will need concrete examples of the differences when software is run on
two different systems, because the ROMs are identical. The problems
exhibited here may be a result of a drive problem (discussed in the "slows
down" section below).

RAM Disk
--------
It sounds as if you are using the Classic Control Panel to modify the RAM
disk. The Classic Control Panel is not aware of the memory requirements of
GS/OS and will let the user set unreasonable RAM disk sizes. GS/OS will
re-assign the value as it "takes" memory back at boot time. Using the
Graphic Control Panel will eliminate this problem. This is not a bug,
because the Classic Control Panel is necessary when using the system with
ProDOS-8.

As a side note, pressing Open-Apple-Reset is not a very elegant way to
re-start the system. We highly recommend the use of menu-bar selections
over this method. Use Open-Apple-Reset only as a last-ditch effort.

Disk Access Slows Down
----------------------
The slowdown your customer is experiencing could be a result of
copy-protected software. If other Apple IIGS systems with the same ROMs
(03) load the software more quickly, swap in a disk drive from one of the
other systems. It's possible that the drive is in need of cleaning, and
has troubles reading copy-protected disks.

Again, the ROMs you received are the same as the ROMs shipped in later
systems.


Published Date: Feb 18, 2012