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billdeg
February 2nd, 2010, 06:36 PM
I have an Apple II (S/N: A2S1-33122 ) that always bombs quickly after boot when I attempt to do anything. Sometimes it appears to read the disk but never gets past the Apple ][ screen. Sometimes the system will bomb out to the monitor prompt (*) . In these cases usually a SHIFT+RESET will pop me back to the BASIC prompt ( ] ), but if I write a little program and run it, (a counter or something simple) the computer bombs back to the monitor prompt.. And so on.

I'll figure it out eventually. Maybe it's the power supply, because I am not getting the kinds of symptoms that RAM is the issue. Just thought I'd mention what I have been up to lately.

http://vintagecomputer.net/apple/appleII_A2S1-33122/thm_AppleII.jpg

Bill

Druid6900
February 2nd, 2010, 07:16 PM
It may well be a problem in the last row of ram which doesn't see much use unless you are loading something fairly large, like a DOS.

david__schmidt
February 2nd, 2010, 08:05 PM
A2S1? That is old. They need a little TLC from time to time - you might start by reseating all the chips, focusing especially on the ROM and RAMs.

tezza
February 2nd, 2010, 11:11 PM
Hi Billl,

Yea, I was thinking the higher rows of RAM myself. I had the same symptoms with one of my clones and it was a RAM chip high enough up so that it got past boot, but then crashed soon after when you moved into the RAM space supplied by the faulty chip.

Tez

billdeg
February 3rd, 2010, 04:30 AM
Hi Billl,

Yea, I was thinking the higher rows of RAM myself. I had the same symptoms with one of my clones and it was a RAM chip high enough up so that it got past boot, but then crashed soon after when you moved into the RAM space supplied by the faulty chip.

Tez

That's what I will work on next.

Interesting side note - I have three sets of Apple II ROMs, and when installed, each reacts to the RAM problem differently. Assuming it is RAM. I also replaced a few of the TTL chips that appeared to be bad or going bad. I have plenty of 4116's.

Bill

billdeg
February 3rd, 2010, 12:57 PM
Dumb question - the higher rows of RAM are the ones farthest from the keyboard. The same row as is used to attach the 16K card connector?
Bill

tezza
February 3rd, 2010, 01:40 PM
Dumb question - the higher rows of RAM are the ones farthest from the keyboard. The same row as is used to attach the 16K card connector?
Bill

Yes. That's the highest row.

Tez

billdeg
February 3rd, 2010, 05:05 PM
I swapped every RAM chip with two others for each slot. That technique will not be perfect, if I have more than one bad RAM, but it's a buckshot approach. I also swapped out the ROMs and selected TTL 74L chips. I also traded processors.

I nearly consistently get dropped to the monitor prompt and it looks like this:

0005- A=00 X=00 Y=18 P=B4 S=FD

after a few seconds I get an OS error that makes no sense:

LANGUAGE CARD CANNOT BE RELOADED UNTIL SYSTEM IS REBOOTED

(there is no language card, and I have swapped the memory card without effect)

weird.

bd

tezza
February 3rd, 2010, 05:23 PM
weird. I wonder if some faulty capacitor is pushing the circuit out of tolerance somewhere as it heats up, and hence tipping the machine into the monitor?

Sounds like it could be a heat related problem and if it's not because of the RAM access eventually being required, it could be a cap?

One of my machines worked for about 30seconds then crashed. I traced it back to a faulty capacitor. It never threw me into the monitor though ,,but then I guess the symptom would depend on just what cap might be affected.

Tez

tezza
February 3rd, 2010, 05:30 PM
after a few seconds I get an OS error that makes no sense:

LANGUAGE CARD CANNOT BE RELOADED UNTIL SYSTEM IS REBOOTED

(there is no language card, and I have swapped the memory card without effect)

weird.

bd

Biill, when you say you have a memory card, is that a 16k one in slot zero? If so, then it is often referred to as a language card, primarily because you needed it to run things like Pascal. The name "language card" stuck for this 16 memory expansion card. That's what the message will be refering to.

Whether or not the problem has got anything to do with it, is another question. If you have swapped it, probably not.

Tez

Tez

billdeg
February 3rd, 2010, 05:41 PM
If I may add to the weirdness, I can boot and run with no problems an adventure game called "MoonMist" and I know the other disks are OK. Standard DOS 3.3 stuff. Is it possible that this Apple II is too old to boot DOS 3.3?
Bill

billdeg
February 3rd, 2010, 06:30 PM
Good news.

1. At least one of the ROMs that came with this system is bad, confirmed by installing in another system. Original system did not come with ROMs for spaces D0 and D8, but I understand that these are optional.

Came with Integer BASIC ROMs - One of these does not work, no way to test.
3410003 - F0
3410002 - E8
3410001 - E0


2. Noticed that the set of ROMs taken from the newer spare Apple II board were in the wrong order (I got the board that way). I was making the assumption that the ROMs were in the correct order. When I installed into the Apple II, that was the source of the weirdness.

3. When I put the replacement ROMs in the correct order, system worked. I like the original ROMs, but I'd rather have a working system, or at least know that everything else works. I will leave the newer ROMs insalled for now. I assume there is no place to get the old integer BASIC ROMs.
Bill

tezza
February 3rd, 2010, 09:01 PM
Glad you got it sorted Bill

Tez

bugman2112
February 4th, 2010, 04:26 AM
These guys:

http://www.reactivemicro.com/

Will burn you a new set at a reasonable price. You can go with the original monitor and interger basic, or the more modern applesoft and monitor. The applesoft option will give you the best compatability with everything, but may not be the best choice for "stock"
configuration of your machine.

billdeg
February 4th, 2010, 07:45 AM
interesting - but then is a new copy of the original ROM more authentic than a newer but original ROM?

channelmaniac
February 4th, 2010, 07:50 AM
I have a stack of older Apple II ROMs. Give me the part # off the top of the chip and I'll dig to see if I have one.

RJ

billdeg
February 4th, 2010, 07:55 AM
One of these three integer BASIC ROMS is bad, but I don't know which

ROM E0 3410001
ROM E8 3410002
ROM F0 3410003

Bill

channelmaniac
February 4th, 2010, 08:19 AM
Do you have an EPROM programmer? If so, you can read those chips in and check the checksums against known good dumps.

RJ

billdeg
February 4th, 2010, 08:30 AM
I need a programmer, it's on my list. Are these 2716's?

channelmaniac
February 4th, 2010, 09:23 AM
No. They are 9316B which have a different pin configuration for the program & enable lines. For example, pin 18 is tied high on the 9316 where it should be low to read on the 2716/2516. Also, pin 21 on the 9316 is tied low to read where it should be tied high on the 2716.

So, to use a 2716 in place of the 9316 you need to swap pins 18 and 21 You can do this by stacking sockets and using some jumper wires to move the signals to where you want/need.