umsmit72@ccu.umanitoba.ca (Kenneth G. Smith) (03/27/91)
I was wondering if there is anyone out there who can help me with
a loading problem I'm having with my Apple II+. When I boot DOS,
the Applesoft BASIC interpreter seems to crash as soon as it tries
to execute any of the lines in the 'HELLO' (DOS 3.3) or the
'Startup' (ProDOS) program. Using 'TRACE', I can see that it
bombs on pretty well the first executable line (it does, however,
execute 'HOME' and 'TEXT' alright). It seems prone to crash on
'PRINT' statement and when trying to 'DIM'ension an array.
This causes me to be thrown into the monitor ('*'-prompt) each and
every time I startup my system. A few peculiar exceptions to the
rule are when I boot my 'AEPro' comm. program which boots fine,
activates my 80-col card, and executes flawlessly (actually my
CP/M OS does likewise ie. works).
At the BASIC prompt (after <cntl>-C'ing out of the monitor), I
can't seem to run any BASIC programs without hanging the computer.
Sometimes DOS commands such as 'CATALOG' give me a syntax error,
sometimes not.
Does this sound like a possible motherboard problem? I don't
really want to replace it only to find that it's a memory or I/O
problem that could be fixed with a simple chip swap. Why will
some canned software (AEPro (PRODos) and Bank St. Writer (DOS 3.3))
run flawlessly, while other programs crash on the first statement?
Any suggestions or trouble-shooting techniques would be appreciated.
Thx,
Ken Smith
--
=-=-=-=-=-=-=-=-=-=-=-=-= umsmit72@ccu.umanitoba.ca =-=-=-=-=-=-=-=-=-=-=
"Just because your voice reaches halfway around the world doesn't mean
you are wiser than when it reached only to the end of the bar."
----------------------------------------------------- Edward R. Murrow --jeffb@world.std.com (Jeffrey T Berntsen) (03/28/91)
umsmit72@ccu.umanitoba.ca (Kenneth G. Smith) writes: >I was wondering if there is anyone out there who can help me with >a loading problem I'm having with my Apple II+. When I boot DOS, >the Applesoft BASIC interpreter seems to crash as soon as it tries >to execute any of the lines in the 'HELLO' (DOS 3.3) or the >'Startup' (ProDOS) program. Using 'TRACE', I can see that it [stuff deleted] >Does this sound like a possible motherboard problem? I don't >really want to replace it only to find that it's a memory or I/O >problem that could be fixed with a simple chip swap. Why will >some canned software (AEPro (PRODos) and Bank St. Writer (DOS 3.3)) >run flawlessly, while other programs crash on the first statement? Sounds like it might be as simple as a loose, dirty, or bad Applesoft ROM chip. Open the cover on your ][+. Look underneath the front ends of the disk controller & other cards you have there. You should see a row of six chips about 2 1/2 by 3/4 inches each. The five on the right are your Applesoft ROM's. The one on the left is the Autostart ROM. Let's assume for now that they're just loose. Make sure the Apple is powered off and unplugged (just to be safe). Remove all the cards from the slots, remembering which ones were where. With your thumb, firmly press in the center of each of the ROM chips. If you hear a mild pop, the chip was loose and you've reseated the chip in its socket. (If you hear a loud crunch, you've pressed too hard and your thumb is now on the wrong side of the circuit board. ;-) Replace the cards the way they were before I coaxed you into messing with the insides of your Apple. Plug in the power cord and turn it on. If the Apple works, that's all you will need to do. You may need to do this every once in a while, depending on the age of your machine. My ][+ was made in Jan. 1979 and needs chips reseated about every 2 months. If that didn't take care of it, it's time to assume that a loose ROM chip wasn't the problem. The next most likely problem is that one of the pins on the ROM chips is dirty. You'll need to break into your machine the way you just did to reseat the chips (power off, unplugged, cards out). With a small flat blade screwdriver (jeweler's screwdrivers are perfect for this) pry each of the chips out of the sockets. Be VERY CAREFUL not to bend or break any of the pins. Don't take all of the ROM's out at once. That will eliminate the problem of remembering which one goes where. Once you have the ROM out, take a look at the pins under a strong light. If the pins look light, bright, or shiny, they're in good shape. If they're brown, black, or a powdery white color, they need to be cleaned. The best cleaner is the type of cleaner used for cleaning tape heads, as it doesn't leave a residue. The bottles of cleaning solution that come with disk drive cleaning disks will work fine. Wet a cotton swab with solution and GENTLY swab the ROM's pins, both outer and inner sides. Don't worry about between. If the cleaning solution removes gunk (or goop) from the pins, you're all set and can replace the ROM. If the cleaning solution didn't work, you can use a pencil eraser to GENTLY rub the gunk from the pins. Once you use an eraser, you will need to use the solution to remove eraser residue from the pins (just brushing away the crumbs isn't enough). You should now have a clean ROM. Replace the rom in the socket you removed it from. Be sure to line up the pins with the holes in the socket. The notch on one end of the chip should be facing toward the keyboard. Using your thumb, press the ROM into the socket being VERY CAREFUL not to bend any of the pins in the process. Repeat this process for each ROM. If, after getting everything together, you have the same problem, it is likely that you have a bad ROM and will need to find a replacement. (But that's another problem.......) It's also possible that one of the chips in the area of the ROM's has the same kind of problem we thought the ROMS might have had. You can try reseating or cleaning those. Concentrate on the ones on either side of the ROM's labeled 74LS138 or 74LS139. One of those controls the computer's access to the ROM's (but I forget which one.) Some programs , such as AEPro, some games, etc. work because they don't use Applesoft at all. Hope this was some help! ----------------------------------------------------------------------------- Jeffrey T. Berntsen | looking for a good .sig jeffb@world.std.com | -----------------------------------------------------------------------------
alfter@nevada.edu (SCOTT ALFTER) (03/28/91)
In article <1991Mar27.233329.13287@world.std.com> jeffb@world.std.com (Jeffrey T Berntsen) writes: >for now that they're just loose. Make sure the Apple is powered off and >unplugged (just to be safe). Remove all the cards from the slots, remembering ^^^^^^^^^ Actually, it's best to leave the computer plugged in. This will keep static from zapping chips; any static buildup you might be carrying will go down the cord and to the ground pin in the power outlet. With the machine unplugged, static has nowhere to go. As you said, though, the computer must be turned off. If you start playing with the chips while the computer is turned on, you're guaranteed to fry something. Scott Alfter-----------------------------_/_---------------------------- Support Operation Apple Storm! / v \ Apple II: Internet: alfter@uns-helios.nevada.edu ( ( the power to be your best! GEnie: S.ALFTER \_^_/
richm@pro-berks.cts.com (Rich Mlodoch) (03/30/91)
In-Reply-To: message from umsmit72@ccu.umanitoba.ca Sounds like bad Applesoft ROMs to me. The thing the programs that work all have in common is that they don't use the Applesoft ROMs to opperate. There's a program out there called AppleCillin that will check your Applesoft ROMs. I'm sure you can find an old ][+ out there that's not being used that you can get the Applesoft Roms from. There are also some Mail order places that sell the ROMs. Shreve systems (or something like that comes to mind) has them in Shreveport Loooisianna. ProLine: richm@pro-berks Internet: richm@pro-berks.cts.com UUCP: crash!pro-berks!richm pro-berks--215/929-4315--A free UUCP/Internet system