[Atari Buy/Sell/Swap/Trade Event August 5th 10am-2pm 15 miles SE of Charlotte, NC]

I'll plan on being there.

 

Might be able to bring a few things if I can get them from storage.  We are in the middle of a move. 

[FS: ColecoVision Game Collection! Will Separate/Bundle Deals! UPDATE!]

PM'ed

[Atari 800 Joystick Port 1 Problem]

On 5/6/2022 at 11:10 PM, Panther said:

It's compatible with a number of different PIA chips, including from various Atari systems (any C01495) or even the W65C21N, at least for the most part (not in a 576NUC+ if you want to be able to program the PIC while the PIA is plugged in).

 

 

It's weird, because I pulled the 800 PIA and plugged it into the 1200xl and it wouldn't boot at ALL.  I put the original 1200xl PIA back in and the 1200xl booted fine.

[Atari 800 Joystick Port 1 Problem]

Maybe the PIA chip.

 

Is the PIA from the 1200XL compatible with the 800? 

 

The PIA in the 1200XL is CO14795-12, the 800 is just CO14795.

 

 

[Atari 800 Joystick Port 1 Problem]

I recently picked up an Atari 800.  Upon testing further, it seems to be working fine except for the joystick port 1.

 

When a plug in a known good joystick, the ship in Atari Blast or any other game will move to the far right and not move.

 

What should I look at checking first to fix this?

 

POKEY chip?  It generates sound just fine, but this chip also reads the joystick ports, correct?

 

[Atari 5200 PS Voltage - Indus GT Replacement]

Any recommendations or links to good modern power supplies for the Indus and for the rest of the Atari line for that matter?

[Atari 5200 PS Voltage - Indus GT Replacement]

So I picked up an Atari 5200 PS to use as a replacement for a failed Indus GT drive power supply.

 

I'm reading around 14.4V from the plug with no load.  Supposedly this is a 11.5VDC power supply, is that a safe voltage reading with no load?

[Free Atari 800XL setup to a good home]

Wasn't me, although I was going to go pick it up.

 

Guess he wanted to get rid of it quick, because he gave it to a more local person after communicating to me that I could pick it up.

[Free Atari 800XL setup to a good home]

PM Sent!

[Atari 1200xl Repair and Fujinet Funkiness]

39 minutes ago, damosan said:

I'd run a memory test in a loop for a bit.  This gives the machine time to warm up as you're looking for hot chips.  I had a 130XE that had ram issues in the high bank.  Running Star Raiders was ok - loading stuff that required more than 64k would introduce weirdness - screen artifacts, locks, etc.

 

I wrote a cc65 program to scan the bank - as time progressed it identified more and more bad bits.  Some would lock high...some low.  I had the memory replaced and everything was good.

 

 

I did let it run through a memory test twice and even checked the memory out of the system with a ram checker I built.  

 

I'll let it run some more memory checks for a good while to see if it is a heat problem.

 

I also have a UAV upgrade I want to do on this one but would like to see a stable system before upgrading.

[Atari 1200xl Repair and Fujinet Funkiness]

7 hours ago, Sugarland said:

Have you checked voltages on your PSU? How do your capacitors look? Are they leaking or bulging?  Have you tried swapping all of your RAM chips to see if that improves things?

Oh yes, all of this was checked before getting to the CPU and ANTIC. I used a logic probe to look at all the address and data lines.  Found out that A7 was held high or low (cant remember now) instead of pulsing.  I also pulled and reseated all ram.  And pulled all ram and tested externally on an arduino tester.

 

 

[Atari 1200xl Repair and Fujinet Funkiness]

6 hours ago, _The Doctor__ said:

you may need to give time for chips to draw down give a good 8 or 11 count

Yeah, I did wait a good 10 to 30 count before powering back up.

[Atari 1200xl Repair and Fujinet Funkiness]

Hey guys,

 

I've been working on fixing up my Atari 1200xl.  Diagnosed it to a bad CPU and possible ANTIC.  I ordered both chips from myatari on ebay.  After a back and forth, I got the chips in.  Popped in the new CPU and voila, my Atari 1200xl was back up and running.  Not so fast....

 

While it was working great with the Pole Position cartridge, after a few more boots and hooking up the Fujinet, I started to get some weird graphic artifacts and the Fujinet would lock up on connecting to WiFi.  So, I go and replace the ANTIC chip.  Success!  I am able to boot into Fujinet and actually load some files.  Not so fast....

 

After booting into some games, watched a demo, I started to get this funkiness.  When finished with the current program, I would power off the Atari 1200xl, power it back on, and just a black screen.  Nothing, no Fujinet boot.  Power cycle a few more times, still nothing.  Removed the Fujinet.  Power cycle, still black screen.  Pop in the Pole Position cartridge, and bam, back up and running.  So I go back and insert the Fujinet, it powers up fine.  So.. let's load up some SALT or tests.  They work and all tests are passed.  Power cycle to go back to Fujinet and Not so fast.. black screen again.  If I remove the Fujinet, pop in Pole Position it comes back.

 

What could it possibly be at this point?  Is there a delay-line reset chip I need to look at?  

Suggestions what to tackle next?

 

Oh, and I'm going to have to do the mylar fix on the keyboard too.

 

 

[New 65/130XE keyboard mylars]

I need one of these for my 65xe.   Are they still available for sale in US or do I need to order from Europe?

 

Already sent a PM to MacRorie.

[Atari 800XL and 130XE computers for sale with lots of era software and hardware for sale!]

Where are you located?

[FS: Commodore 64, SD2IEC low profile reader, TI99 Speech Module]

I'll take the C64 SD2IEC.

[SOLD: Vader modded with 12 games $99]

PM sent!

[Interest check, Mega ST2, 486 Computer, Atari 65xe, CD-I]

Any work done on the 65XE? I'm assuming no socketed board?

[Atari 1200xl Troubleshooting]

Ok, back for more testing!

 

Since I first posted, I decided to build a little electronics project. Purchased an Arduino board and protoshield, built up a 4164 DRAM tester and program.

 

I have now tested all 8 4164s and according to the DRAM tester program, they have all passed. I also ordered 8 more DRAM just in case, but had fun building the project nonetheless.

 

What's up next to test? I may need to look at purchasing a socketed 800xl so I can swap some of the other chips.

[SDrive-ARM preorder]

Put me down for one assembled unit.

 

Thanks!

[Ultimate Atari Cart (Electrotrains) Pre-Order by 18 APR 17]

Posted to a few Atari and 8-bit specific Communities on Google+.

[Ultimate Atari Cart (Electrotrains) Pre-Order by 18 APR 17]

I posted it on my Google+ feed. A facebook dedicated group may suffice too.

[Atari 1200xl Troubleshooting]

My Atari 1200xl is dead. I've tried two different Atari 9VAC power supplies using a composite video cable that works with my 65XE. Most of the time when I power up the 1200xl it will show a brief artifact, pop, and then show a black screen. Other times it will just show a yellow screen. I inserted and tried powering on with the Pole Position cartridge to no avail.

I popped open the 1200xl and pushed all ICs down to reseat if they had come slightly loose. (After grounding myself.) Tried again, same result. Next, I removed all the RAM chips, moved some around and reinserted them. Same result. I then reseated all the other main chips, POKEY, 6502, GTIA, ROMs. Same result. What's the next best test?

[Ultimate Atari Cart (Electrotrains) Pre-Order by 18 APR 17]

I'm in for one! Paypal sent! I'm going Purple!

[1200XL Owners Club (serial tracker)]

Hi! New guy here. I've got an Atari 1200xl that I saved up and bought when I was young. I'm not sure if it still works. I checked the voltage on the power supply I have and it is overvolted to 11 to 12 volts instead of the 9 volts output it should have. I need to purchase a new one and then test to see if it still powers up. Any good links on troubleshooting a 1200xl?

 

Anyways, Here is the serial number on mine:

 

72 R DA 10201 203