64K 600XL w/n Load Battlezone, but XEGS Will

[bfollowell]

7 hours ago, CharlieChaplin said:

maybe check the OS of your 600XL computer, some of them do have XL-OS Rev. 1 and there are indeed some A8 programs that do not run at all with this OS version. (A friend of mine had a 600XL with 1064 and several programs from Poland did not work with it due to XL-OS Rev. 1.)

 

 

According to the AtariMania 8-bit FAQ, all 600XLs have OS Rev 1, assuming they hadn't been upgraded at some point. I can neither confirm nor deny that it is true, only that it is what the FAQ states.

 

[Sugarland]

5 hours ago, Mathy said:

Hello guys

 

I probably haven't opened one of the cartridge boxes in years.  Just opened the BattleZone box (blue, copyright 1987, XE cartridge, RX8077), stuck the cart into my 64kB 600XL, plugged in the TAC-2 and played the game for a short time.  Everything seems to work just fine.

 

BTW I used the description on my special stuff site to upgrade the 600XL to 64kB (years ago).  The 600XL was made in Hongkong, is a PAL machine and has a sticker at the bottom with French text on it.

 

Sincerely

 

Mathy

 

 

Good info! Maybe this is a case where the SN74LS08 timing chip (U18 I think) is causing rare compatibility issues. It's the horizontal chip directly above the CPU. Consider replacing it with a SN74F08 chip.

 

[gilsaluki]

14 hours ago, Sugarland said:

 

Good info! Maybe this is a case where the SN74LS08 timing chip (U18 I think) is causing rare compatibility issues. It's the horizontal chip directly above the CPU. Consider replacing it with a SN74F08 chip.

 

thanks for the update/info.  Maybe before R2 the timing chip, I can try to reseat them first. 

[gilsaluki]

More weird-ness.  Haven't had the 600XL on for a few days. So today,  I plugged in Battlezone, loaded right up as it should.  Played it a while, no issues.  WHAT?  Plugged in Moon Patrol (also previously wouldn't load), it too loaded right up.  Plugged in a few other carts, all is well.  Thought it fixed its own gremlins.  Plugged BZ back in...No go.  Moon Patrol...no go.  Intermittent issue. Need to reseat the chips?

[Faicuai]

3 minutes ago, gilsaluki said:

More weird-ness.  Haven't had the 600XL on for a few days. So today,  I plugged in Battlezone, loaded right up as it should.  Played it a while, no issues.  WHAT?  Plugged in Moon Patrol (also previously wouldn't load), it too loaded right up.  Plugged in a few other carts, all is well.  Thought it fixed its own gremlins.  Plugged BZ back in...No go.  Moon Patrol...no go.  Intermittent issue. Need to reseat the chips?

No doubt you have a HW problem.

 

Either timing / sync. related, and/or the actual cart-port EDGE connector itself (being the latter the least probably, but can't yet be discarded).

 

To narrow down or discard a physical edge-connector problem, try every single BANKED-cart you have, and make sure that there is consistency on the results (e.g. check those which work and those which don't are always the SAME, or they vary randomly).

 

On the MoBo, I would also look / check / re-seat CO60472 (delay-line), as it may be failing. But can't discard PIA and MMU (C061618)

 

[+Stephen]

There's also the "freeze spray" trick.  With the system apart, if you get it to where the games are glitching, you can turn a can of air duster upside down and spray the various ICs to rapidly cool them.  If things then work, you have a heat related issue.  Could be bad solder joint, could be bad IC.

 

If you do this, try to not get the spray on your fingers.  Burns from freezing spray hurt just as bad as burns from a flame.

[gilsaluki]

Thanks for the inputs. I reseated all the chips and looked for bad solder joints--none noticed with magnifying glass.  No difference.  Really strange how its only some of the XE carts that won't work.  All my other "legacy" carts work.  Some of the XE carts work as mentioned before.  I noticed I had previously had changed out the GTIA back in 2019 (which was probably the last time I fired the computer up).  Don't have any air duster to try the Freeze trick. I did managed to download and run Moon Patrol.  The file for Battlezone on Atarimania is corrupted and the Ultimate cart says its a bad file.  So, yeah, ROM versions from Ultimate Cart work fine. 

[+x=usr(1536)]

4 hours ago, Stephen said:

If you do this, try to not get the spray on your fingers.  Burns from freezing spray hurt just as bad as burns from a flame.

Quoted for truth.  Been there, done that, came to the conclusion that the only way I'd ever want to experience that again was if, for some reason, i had to obliterate my fingerprints from my fingers.  Even then it would be one of the last possible picks.

[+DrVenkman]

19 minutes ago, gilsaluki said:

The file for Battlezone on Atarimania is corrupted and the Ultimate cart says its a bad file.  So, yeah, ROM versions from Ultimate Cart work fine. 

Atarimania has two versions - the official Atari North American release in a .ROM format. It probably needs a .CAR header appended to use on the Ultimate Cart. There is also a Homesoft conversion of the 5200 version. That file as a .COM extension when you download it. Change it to .XEX and it will load, though I don't know about the memory requirements. I just tested it quickly on my 576NUC+ and it seems to work fine.

 

EDIT: Just loaded it on my PAL 1088XLD set to 64K and it runs fine there too, thougha bit slower than on my NTSC machine. 

 

 

BattleZone [5200].xex

[gilsaluki]

UPDATE, or chasing my tail.  Symptoms now.  Sometimes Battlezone, Moon Patrol will load and run (rarely).  Normally those two carts just go to black screen.  I moved the 600xl over to my other station (other power supply, CRT setup).  ALL the carts worked first time. Hummmm, maybe it was the power supply or something.  Swapped the PSU out on the other workstation (one with the LCD flat screen), no good.  Moved it back to the CRT workstation, it worked.  Now confused. How could the display type (CRT vs Composite LCD) have ANYTHING to do with this?  I tried all my carts, and at this time (on the CRT station) every cart worked.    Then it didn't, same symptom, same carts refusing to load (BZ and Moon Patrol).  The screen on those two carts go to black screen.  

Actions so far:

1. Reseated all the chips

2. Checked for bad solder joints

3. Tried multiple carts, only a few select XEGS types don't load (sometimes they do as I played BZ for 30 mins last night on the Composite LCD station).  Powered down, waited for RAM to deplete, Power back up...Black screen again).

4. Swapped out power supplies (and checked voltage and ground output of the connector...getting 5.21 VDC out of the proper pins)

5. Felt for Hot chips, nothing stands out

 

Could it be the Delay chip (C060472)?  Something with the timing circuit?

[Sugarland]

With my 800XL that had issues fixed by replacing the SN74LS08 with an SN74F08 the issue wasn't the chip exactly. Swapping the SN74LS08 from the buggy machine into another machine did not reproduce the issue on the other machine. And swapping a known good machine's SN74LS08's into the buggy 800XL did not fix it. However when the SN74LS08 was replaced with the SN74F08 that fixed the symptoms (The!Cart was crashing or failing to work correctly). So in this case it was an issue that was difficult to narrow down but the new timing chip absolutely fixed the symptom.

Edited May 1, 2021 by Sugarland

[gilsaluki]

(Cont)

6. Swapped out (U7)  74LS08NX

7. Swapped out (U10) C014806-12, seemed warm (6502 chip)

8. Swapped out (U13) C0604472, Delay Module

Still intermittent.  Will not load some XEGS carts, loads most, just not (BZ, Moon Patrol, some others).   Then sometimes after non-use, it will load and play them.  Switch off, then will not.  Nothing seems warm/hot to touch.  Baffled. 

[Sugarland]

2 hours ago, gilsaluki said:

(Cont)

6. Swapped out (U7)  74LS08NX

 

Swapped it out with what? 

[gilsaluki]

8 minutes ago, Sugarland said:

Swapped it out with what? 

With same numbered chip from a know good board. But, I do have a couple of SN74F08 on order to try what you suggested Sugarland.  Thanks for the input.  I will keep you posted.  Hoping that will solve the issue. While in there, I again looked at all the connections I made for the 64K upgrade.  All look really solid, good solder joints, etc.  Ran a Memory test again, checks good, as do all the other build-in tests.  Really bugging me why it is intermittent, refusing to load just a few of the XEGS-era carts.  Again, some DO load, a select few will not (most times). 

[gilsaluki]

On 5/1/2021 at 1:32 AM, Sugarland said:

With my 800XL that had issues fixed by replacing the SN74LS08 with an SN74F08 the issue wasn't the chip exactly. Swapping the SN74LS08 from the buggy machine into another machine did not reproduce the issue on the other machine. And swapping a known good machine's SN74LS08's into the buggy 800XL did not fix it. However when the SN74LS08 was replaced with the SN74F08 that fixed the symptoms (The!Cart was crashing or failing to work correctly). So in this case it was an issue that was difficult to narrow down but the new timing chip absolutely fixed the symptom.

Fix! Problem solved. Received the 74F08 I ordered.  Took out the 74LS08 (U7), installed the 74F08 (U7). That fixed the issue.  Now the 64K-Upgraded 600XL will now load all the XEGS CARTs, Battlezone and Moon Patrol included.  Thanks Sugarland for the fix!

[Sugarland]

3 hours ago, gilsaluki said:

Fix! Problem solved. Received the 74F08 I ordered.  Took out the 74LS08 (U7), installed the 74F08 (U7). That fixed the issue.  Now the 64K-Upgraded 600XL will now load all the XEGS CARTs, Battlezone and Moon Patrol included.  Thanks Sugarland for the fix!

Great to hear it fixed the issue. You're welcome! Keep that 74LS08 though. It's probably not a bad chip.  Someone else here on AA suggested that a couple years ago so I can't take much credit.

[+DrVenkman]

The 74LS08 chip in an A8 buffers the Phi2 clock signal generated by SALLY and makes it available to the rest of the system. The signal is buffered to create sharper/faster rise- and fall-times on the clock to help synchronize bus activity across the system. The F version of the chip is faster-responding than the LS series original. 

 

It would be interesting to take some oscilloscope readings of the Ph2 clock signal with the 74LS08 in place, and then compare them to readings after swapping it for the 74F08. 

[Mathy]

Hello Herb

 

33 minutes ago, DrVenkman said:

It would be interesting to take some oscilloscope readings of the Ph2 clock signal with the 74LS08 in place, and then compare them to readings after swapping it for the 74F08. 

 

It would be equally interesting to take some oscilloscope readings of the signals going into the 74*08, to see where the timing differences in gilsaluki's 600XL come from compared to (his) other 8 bit computers.

 

Sincerely

 

Mathy

 

 

[+DrVenkman]

3 minutes ago, Mathy said:

Hello Herb

 

 

It would be equally interesting to take some oscilloscope readings of the signals going into the 74*08, to see where the timing differences in gilsaluki's 600XL come from compared to (his) other 8 bit computers.

 

Sincerely

 

Mathy

 

 

Well, there's only one place it CAN come from - SALLY pin 39. So it could be some normally-insignificant variability in SALLY chips that is not being properly smoothed-out by buffering Phi2 as intended, or it could be marginal sockets for either SALLY or the 74LS08 causing some slightly higher resistance and futzing with the timing juuuust enough to mess with some carts. 

[gilsaluki]

I will dig out that 74LS08 from the trash.  You are correct, it isn't necessarily bad (I forgot that I swapped it from another board earlier in the troubleshooting process. Thanks to all, I have learned some things this go round.  

[Sugarland]

3 hours ago, gilsaluki said:

I have learned some things this go round.  

 

It's the meta game and just as much fun.

 

[gilsaluki]

14 hours ago, Sugarland said:

 

It's the meta game and just as much fun.

 

It sometimes makes me go gray (er).  Bald (er).   Scheeeezzzz.  Sometimes.