FPGA CatBox vs. SpaceDuel pcb

Smitty420

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So I recently acquired an fpga catbox to help me repair a Gravitar PCB, and decided to learn about using on a couple of spaceDuel boards. One of the boards is confirmed working and the other does not display vectors but play blind.
I hooked up the working board and it passes all the tests with no problem. When running tests on Not Working board it passes all tests up to the vector generator section and then I get some problems running traces. When running a test for
Center, draw long vectors and then halt gives me a couple of halt commands instead of VCTR in the first two commands. Somewhere I have problems with these two lines but not sure where to go from here. Any suggestions would help.

I am also trying to get signatures from the schematic but not sure where to tie the start/stop and clock lines. I am assuming that they are the same as Gravitar but some advice is appreciated.

IMG_1027.jpeg
 
Are the times off when running the various standard tests?
 
Are the times off when running the various standard tests?
Not that I can tell, they all look good. Compared to good board which passes those tests including this trace test. So compared to a good PCB with the cat box finding out why these signal traces are different might solve my board problem. Now I am trying to find something the good board is doing that the bad one is not. I truly do not think that this problem is in the analog output section but I am real close to socketing that section and comparing sides but I really think the problem is before the DACs.
 
Have you looked at the videos Fred has? They do some with Space Duel.
 
I've always found the CENTER test is key. Got to get all the timings correct on each counter.
Don't go any further until this passes.

Follow the steps in the latest manual:

VG Center: Now that you have the halt working, you can try to center the beam. On an analog vector generator (anything but Asteroids, Asteroids Deluxe, Lunar Lander) This should take about 89 microseconds or so (probably anywhere around this is fine). This uses some of the vector timers to zero the integrators. If this fails then you have a vector timer problem. I forget what I did on the digital vector generator for this test but I don't think it really applies (it will do something but not something very useful if I remember – maybe just go to the center?).

Center_test.jpg
 
Have you looked at the videos Fred has? They do some with Space Duel.
Yes, that is where I started when I got the thing and thought it was convenient that I was working on SpaceDuel.



I've always found the CENTER test is key. Got to get all the timings correct on each counter.
Don't go any further until this passes.
I was looking to run this down as I saw it n the video but the information was not in the notes on the software version and files I am using. Both my boards showed this test to time correctly so I assumed it was all ok.
Will trace the signals down next and see if numbers match.
 
There should be an AVG Test Notes.txt file in the Atari AVG folder.. It has all of the timings.
Space Dual should have these

Halt and Center are the tricky ones.. Usually once you get them the others are fine
If your Analog section is good - then it is after the VG and before the analog.

VG Halt - 2.175us
VG Center - 89.45
VH Drawshort from Ram - 178.05
VG Draw from RAM - 454
VG Draw Single Short Vec frm Ram - 26.55

If you are not getting these times.. these need to work first.
 
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