Atari Touch Tablet, not working on my 800XL...

[leech]

Yet it works on one of my 800s and 130XEs (I haven't tested the other two, nor my other 8bits yet, but it doesn't work on my original 800XL).

Fun thing is, my stock 130XE has kind of a crap video output.  Long vertical lines coming out of it when using Composite or S-Video.  The 800XL looks fantastic in both (well as good as composite seems to get) and after I patched in the wire for Chroma, it looks really good.  But Atari Artist is rather crap with the Touch Tablet not working.  The buttons all work, but when touching the stylus or with my finger, it doesn't move.

 

With the stock 130XE, I went through and tried RAMbrandt, Diamond Desktop and Blazing Paddles, and none of them seemed to work correctly (RAMbrandt and Blazing Paddles both just moved the cursor up). 

My guess is that there is some weird inconsistencies on the systems, guess I could try the same software on the 800XL and 800 to see if it is the same issue.

 

Any ideas?

[_The Doctor__]

completely confused, does it work properly on any machine?

are your machines putting the proper voltage out at the joypad ports?

if yes then it's pokey, PIA, support chips in that order, with the caveat that the passive parts like coils, resistors, and caps connected to the joypadio ports aren't crispy ( I've seen a couple 800XL's with crispy port parts ) last stops are GTIA and the rest of the chips

Edited March 22, 2020 by _The Doctor__

[Rybags]

From memory the X/Y pos of the surface comes over the POT lines.  The tablet buttons come through the paddle buttons aka the stick left/right directions and the stylus button is the stick trigger.

 

You could try a simple Basic program to test the inputs:

 

10 ? PADDLE(0),PADDLE(1),PTRIG(0) ; PTRIG(1), STRIG(0) : GOTO 10

 

For testing in port 2, change the parameters to the controller functions to 2,3,2,3,1 in that order.

PIA problems would see the tablet buttons not work.  GTIA problem would see the stylus button not work.  POKEY or external cap dump problem would see the X/Y surface not work.

[leech]

2 hours ago, _The Doctor__ said:

completely confused, does it work properly on any machine?

are your machines putting the proper voltage out at the joypad ports?

if yes then it's pokey, PIA, support chips in that order, with the caveat that the passive parts like coils, resistors, and caps connected to the joypadio ports aren't crispy ( I've seen a couple 800XL's with crispy port parts ) last stops are GTIA and the rest of the chips

Yes, it works in Atari Artist on both the 130XE and 800.  On the 800XL, the buttons are working, but the stylus/touch to move the cursor does not.  I will try to check the voltages to the ports, and see if anything is crispy.

2 hours ago, Rybags said:

From memory the X/Y pos of the surface comes over the POT lines.  The tablet buttons come through the paddle buttons aka the stick left/right directions and the stylus button is the stick trigger.

 

You could try a simple Basic program to test the inputs:

 

10 ? PADDLE(0),PADDLE(1),PTRIG(0) ; PTRIG(1), STRIG(0) : GOTO 10

 

For testing in port 2, change the parameters to the controller functions to 2,3,2,3,1 in that order.

PIA problems would see the tablet buttons not work.  GTIA problem would see the stylus button not work.  POKEY or external cap dump problem would see the X/Y surface not work.

Perfect, I can give that a shot.  I think it was RAMbrandt if I changed the option in there that the tablet worked, but up/down position was flipped.  This was on the 130XE. 

[Rybags]

Touch not working - then it's the POTs.  It might be a low or missing +5V line on the port there.  Other functions working means the GND is probably OK.

If you're in there then may as well lift and reseat Pokey as well.

[leech]

It seems to sort of do something.  When I touch it, it jumps from 228 to 5, and randomly hits other numbers as I move my finger / stylus around. 

[leech]

The culprit was pin 5!  It was broken within the joystick port.  So for now I stole the one from my 7800 that is just a bare motherboard anyhow (I have a spare).  Ordered some new ones, to replace that one. 

 

Now it's working   I also noticed the other joystick port on my 800xl has part of it's plastic broken off, so I can replace that as well when the new ones come in.

[Nickolasgaspar]

I am experiencing the same  issue...it works on a 65XE but not on a 800XL(XLF). From what I read in here I have to switch most of the ICs in order to find the issue. But first I will check the 9pin port and the passive components of its circuit.

Did you manage to use your tablet with RAMbrandt?

[leech]

4 hours ago, Nickolasgaspar said:

I am experiencing the same  issue...it works on a 65XE but not on a 800XL(XLF). From what I read in here I have to switch most of the ICs in order to find the issue. But first I will check the 9pin port and the passive components of its circuit.

Did you manage to use your tablet with RAMbrandt?

Yeah, it eventually worked after replacing the port with the broken pin.  Pretty sure I tested that one, it has been a while.

[Nickolasgaspar]

So in my case, I bought and repaired a tablet. It works on a 800xl and 900xlf(65xe) board but it refuses to work on the 800xlf board. I checked  the +5V pin on the joystick port and I replaced all the ICs one at a time but still nothing. The resistors and caps appear to be ok. Any ideas?

[leech]

2 hours ago, Nickolasgaspar said:

So in my case, I bought and repaired a tablet. It works on a 800xl and 900xlf(65xe) board but it refuses to work on the 800xlf board. I checked  the +5V pin on the joystick port and I replaced all the ICs one at a time but still nothing. The resistors and caps appear to be ok. Any ideas?

I'd just verify all the continuity between the pins and the board.  Within the db9 socket was where my pin was broken, so one of the axis were not responding.  Sounds like a similar issue.

[Nickolasgaspar]

On 1/8/2022 at 4:27 AM, leech said:

I'd just verify all the continuity between the pins and the board.  Within the db9 socket was where my pin was broken, so one of the axis were not responding.  Sounds like a similar issue.

The update is....the Pokey was bad. I was tricked by 3 different Pokeys and their incompatibility issues between 3 boards? One pokey chip works great (touch tab)  in all three boards.

The second pokey   in just two boards and the last one  doesn't recognize  tab inputs in all three boards.

Really weird ....