Atari 600xl green and beige screen

[The Mr. Video]

Hi. My Atari 600xl came in today but when I turned it on, I get a green (sometimes beige) screen. Any help would be nice.

[+mytek]

Might need to adjust the color pot...

 

 

- Michael

Edited May 26, 2017 by mytekcontrols

[The Mr. Video]

Might need to adjust the color pot...

 

 

- Michael

Just tried that, didn't work.

[Joey Z]

Do you mean *just* the solid color? No READY prompt or self-test?

[The Mr. Video]

Do you mean *just* the solid color? No READY prompt or self-test?

Yes.

[Joey Z]

usually this happens when the OS isn't even running. Try reseating chips, it's about all you can do without a machine to swap parts from.

[russg]

Hi. My Atari 600xl came in today but when I turned it on, I get a green (sometimes beige) screen. Any help would be nice.

not much you can do.

You could hold OPTION when you turn it on. This will disable the BASIC chip, in case

it is bad. It should give you a blank blue screen.

If it comes up the same, then maybe BASIC is bad.

Might be the OS ROM chip. Might be lots of stuff I don't know about.

You only have 16k RAM, that could be bad too.

Edited May 26, 2017 by russg

[The Mr. Video]

Ok it's displaying a redish-brown screen now.

[+mytek]

Ok it's displaying a redish-brown screen now.

 

When you originally posted I didn't realize that you were looking at a blank screen, otherwise I wouldn't have suggested adjusting the color pot. Anyway I agree that it sounds like the OS isn't booting up, which as suggested by others could be caused by any number of things, and all of the suggestions such as reseating chips are good ones to do. But one thing that the 600XL's are famous for is the RAM failing. Touch each RAM chip and if they are particularly hot, especially if one is more hot than another that is probably the culprit and needs to be replaced. If I recall correctly there were two different manufacturers used for the RAM, with one being notorious for failures. If you end up having to replace the RAM you might want to entertain the notion of getting 64K chips and doing this simple upgrade.

 

==============================================================================

                 HOW TO UPGRADE YOUR ATARI 600XL TO 64K RAM

THIS MOD IS COPYRIGHTED BY KEN SUMRALL.  HOWEVER, YOU MAY FREELY
DISTRIBUTE IT, AND MODIFY IT, AS LONG AS THIS NOTICE IS INCLUDED
IN ITS ENTIRERTY.  THE AUTHOR MAY BE REACHED AT THE FOLLOWING
EMAIL ADDRESSES:
     ken%hpda@hplabs.hp.com
     ...!hplabs!hpda!ken

You will need the follow parts to perform this mod:
     (2) 4464 RAM chip, 64Kx4, 150ns or faster.
Additionally, you will need chip pullers, a soldering iron, and 3 small
pieces of wire.  I used wire wrap wire when I did this mod.

If the chips on your 600XL are socketed, you're in luck, otherwise, you need to
first unsolder the following chips:
     (1) 74S32 location U18
     (2) 74LS158 locations U5 and U6
     (2) 4416 locations U11 and U12
and put sockets on the mother board in their place to make the job easier.

Now bend up pin 9 on the 74S32, and put it back in its socket on
the mother board.  Bend up pin 3 on the 74LS158 in location U5, and put it
back in its socket.  Also, bend up pin 10 on the 74LS158 in location U6,
and put that chip back into its socket.  The last two chips you need to
change are the two RAM chips.  Put the 4464 chips into the sockets at
locations U11 and U12 on the motherboard.

Now you need to install 3 wires to complete the mod.  The first wire should
be connected between pin 3 of the 74LS158 at location U5, and pin 20
of the parallel bus on the 600XL.  The second wire should be connected between
pin 10 of the 74LS158 at location U6, and pin 18 of the parallel bus.
The third wire connects between pin 9 of the 74S32 at location U18, and
pin 45 on the parallel bus.  That's all there is to it.

==============================================================================

- Michael

Edited May 26, 2017 by mytekcontrols

[The Mr. Video]

When you originally posted I didn't realize that you were looking at a blank screen, otherwise I wouldn't have suggested adjusting the color pot. Anyway I agree that it sounds like the OS isn't booting up, which as suggested by others could be caused by any number of things, and all of the suggestions such as reseating chips are good ones to do. But one thing that the 600XL's are famous for is the RAM failing. Touch each RAM chip and if they are particularly hot, especially if one is more hot than another that is probably the culprit and needs to be replaced. If I recall correctly there were two different manufacturers used for the RAM, with one being notorious for failures. If you end up having to replace the RAM you might want to entertain the notion of getting 64K chips and doing this simple upgrade.

 

 

==============================================================================

                 HOW TO UPGRADE YOUR ATARI 600XL TO 64K RAM

THIS MOD IS COPYRIGHTED BY KEN SUMRALL.  HOWEVER, YOU MAY FREELY
DISTRIBUTE IT, AND MODIFY IT, AS LONG AS THIS NOTICE IS INCLUDED
IN ITS ENTIRERTY.  THE AUTHOR MAY BE REACHED AT THE FOLLOWING
EMAIL ADDRESSES:
     ken%hpda@hplabs.hp.com
     ...!hplabs!hpda!ken

You will need the follow parts to perform this mod:
     (2) 4464 RAM chip, 64Kx4, 150ns or faster.
Additionally, you will need chip pullers, a soldering iron, and 3 small
pieces of wire.  I used wire wrap wire when I did this mod.

If the chips on your 600XL are socketed, you're in luck, otherwise, you need to
first unsolder the following chips:
     (1) 74S32 location U18
     (2) 74LS158 locations U5 and U6
     (2) 4416 locations U11 and U12
and put sockets on the mother board in their place to make the job easier.

Now bend up pin 9 on the 74S32, and put it back in its socket on
the mother board.  Bend up pin 3 on the 74LS158 in location U5, and put it
back in its socket.  Also, bend up pin 10 on the 74LS158 in location U6,
and put that chip back into its socket.  The last two chips you need to
change are the two RAM chips.  Put the 4464 chips into the sockets at
locations U11 and U12 on the motherboard.

Now you need to install 3 wires to complete the mod.  The first wire should
be connected between pin 3 of the 74LS158 at location U5, and pin 20
of the parallel bus on the 600XL.  The second wire should be connected between
pin 10 of the 74LS158 at location U6, and pin 18 of the parallel bus.
The third wire connects between pin 9 of the 74S32 at location U18, and
pin 45 on the parallel bus.  That's all there is to it.

==============================================================================

- Michael

I don't feel any of the ram chips getting hot.

[+mytek]

I don't feel any of the ram chips getting hot.

 

Then it's likely something else. Too bad you don't have a 2nd machine to swap chips from, since that would make troubleshooting this a hell of a lot easier.

 

- Michael

[The Mr. Video]

Today I tested the PSU because I heard that a bad PSU can cause the blank screen and figured out that the PSU isn't outputing enough voltages. Unfortunately I can't open it up because it's one of those "ingot" PSUs that you can't open up.

[_The Doctor__]

Never use an ingot...

[russg]

I don't feel any of the ram chips getting hot.

If the DRAMs are MT on them, they are bad.

[Bryan]

Solid screen = not running. Time to start swapping chips with a known good machine.

[The Mr. Video]

If the DRAMs are MT on them, they are bad.

What do you mean?

[+DrVenkman]

What do you mean?

 

He means that if you have DRAM chips marked "MT" (Micron Technologies, I think) they're much more prone to failure than other brands and it's a good chance those are bad, causing or contributing to the problem.

[Mclaneinc]

Beige?

 

Seen red, seen green but beige...That's new to me...

 

Are you sure its the ingot, normally the screen colours acknowledge a running machine but with on board issues..

 

BUT, I'm no expert, listen to these guys...

[The Mr. Video]

He means that if you have DRAM chips marked "MT" (Micron Technologies, I think) they're much more prone to failure than other brands and it's a good chance those are bad, causing or contributing to the problem.

Can't find any MT marked chips on my motherboard. Though, I did find one marked MMI. Edited May 28, 2017 by The Mr. Video

[russg]

Can't find any MT marked chips on my motherboard. Though, I did find one marked MMI.

what happens when you hold OPTION when you turn it on?

[The Mr. Video]

what happens when you hold OPTION when you turn it on?

Still get the blank screen, in fact, the first thing I did when I got it hooked up was to try to boot it into self-test.

[Rybags]

Assuming you've done the lift up/reseat on the major chips, I'd assume something's fried, my bet in order would be bad RAM, then CPU, MMU, Antic.

 

A symptom of overvolt PS is buzzing in the audio though similar sound occurs if using RF and it's not tuned in properly.

Edited May 28, 2017 by Rybags

[+DrVenkman]

Today I tested the PSU because I heard that a bad PSU can cause the blank screen and figured out that the PSU isn't outputing enough voltages. Unfortunately I can't open it up because it's one of those "ingot" PSUs that you can't open up.

 

Given your other symptoms, I'm tempted to think that your PSU failed "hot" (overvoltage) and is now not putting out enough current, presuming your earlier voltage measurements were correct. Have you examined the system for blown capacitors inside? Look to see if any of them are swollen or leaking. If you find any, they need to be replaced first thing. Next, get another power supply!

 

Something like this, or one of Bruce's (B&C Computervisions, aka myatari) other recommended versions:

 

http://www.ebay.com/itm/XL-XE-Power-Adapter-1-0A-Orig-New-Atari-Ver-6-The-Logo/140954042315?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26meid%3D6527e4f155cb4d22bce00c4440ee7a41%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D140954042322

 

If you want to salvage the machine, you'll have to try swapping chips one after another to see which one(s) are bad. Good luck!

[The Mr. Video]

Given your other symptoms, I'm tempted to think that your PSU failed "hot" (overvoltage) and is now not putting out enough current, presuming your earlier voltage measurements were correct. Have you examined the system for blown capacitors inside? Look to see if any of them are swollen or leaking. If you find any, they need to be replaced first thing. Next, get another power supply!

 

Something like this, or one of Bruce's (B&C Computervisions, aka myatari) other recommended versions:

 

http://www.ebay.com/itm/XL-XE-Power-Adapter-1-0A-Orig-New-Atari-Ver-6-The-Logo/140954042315?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D40130%26meid%3D6527e4f155cb4d22bce00c4440ee7a41%26pid%3D100005%26rk%3D2%26rkt%3D6%26sd%3D140954042322

 

If you want to salvage the machine, you'll have to try swapping chips one after another to see which one(s) are bad. Good luck!

I don't see any swollen or leaking compositors. Might be a chip problem.

[russg]

Still get the blank screen, in fact, the first thing I did when I got it hooked up was to try to boot it into self-test.

I looked for Red/brown screen in my docs. It said the following:

U2 thru U5, U18, U19, U28, U30. and I would guess Antic or GTIA U7 and U17.

All those mean swapping chips with known good ones.

 

U2 Decoder ; 74LS138

U3 Memory manager

U4 OS ROM

U5 BAS ROM

U18 CO17097

U19 CO61850

U28 Latch 74LS37S

U30 And/Or inverter 74LS51

 

That's not much help, but what I researched about it.

You could take out the BAS ROM and see if you still get the red/brown screen.

It would boot to a blue screen.

I'd start with the OS ROM, Antic and GTIA.

 

If you have socketed chips, that would help a lot.

 

I just tried it, taking the BAS out of a good board. It boots to the self test like you said.

Edited May 28, 2017 by russg