what's wrong with my Hard Drivin repro?

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lidnariq
Posts: 11429
Joined: Sun Apr 13, 2008 11:12 am

Re: what's wrong with my Hard Drivin repro?

Post by lidnariq »

Thank you very much!
FrankWDoom wrote:also rambo 19 is on the same trace as 20, so it's GND for sure.
The ?? in that location is supposed to represent "we don't know whether the pin is an input or a supply pin". Any thoughts on how to make that clearer? I could just add a key, I suppose.
FrankWDoom
Posts: 260
Joined: Mon Jan 23, 2012 11:27 pm

Re: what's wrong with my Hard Drivin repro?

Post by FrankWDoom »

lidnariq wrote:Thank you very much!
FrankWDoom wrote:also rambo 19 is on the same trace as 20, so it's GND for sure.
The ?? in that location is supposed to represent "we don't know whether the pin is an input or a supply pin". Any thoughts on how to make that clearer? I could just add a key, I suppose.
no its probably fine. I get mixed up between how things look on the board and what they actually could be.
icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

Hi, I was wondering if you guys had any play issues? I used a rolling thunder cart this board:
http://bootgod.dyndns.org:7777/image.php?ImageID=1657

prg pin 2 is already mapped to Rambo pin 2. I connected prg 24 to prg 16 and I did chr 30 to Rambo 22

Everything loads fine and plays fine except for in certain areas it glitches. I have removed the 7432, swapped the top white "resistor?" to match the klax board. I even tossed in a resistor/jumper under the 7432. The problem with not having the 7432 is regardless of anything else it is just slightly glitchy all the time. I had even removed the center yellow piece.

Anyhow I put everything back to as it was minus the top white resistor. The game is minty clean looking but soon as you get to first circle ramp bam you get this screen as well as a few other places.
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lidnariq
Posts: 11429
Joined: Sun Apr 13, 2008 11:12 am

Re: what's wrong with my Hard Drivin repro?

Post by lidnariq »

The 74'32 is only there to allow the use of a 28-pin 128 KiB mask ROM.

The "resistor" R2 is a 0-ohm jumper. It looks like it (on the right side) connects to PRG A16, so whether it's necessary should be a function of how you did the rework.
FrankWDoom
Posts: 260
Joined: Mon Jan 23, 2012 11:27 pm

Re: what's wrong with my Hard Drivin repro?

Post by FrankWDoom »

Can you post some pics of your board?

You mention the 7432/jumper swap and one other resistor- did you miss one?
Attachments
tengen64.png
icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

This is all set-up original except the top white resistor I moved from R2 to R1 and just never put it back like I did everything else. The white resistor under the 7432 I did not touch. I thought it may need to be moved but the board is actually slightly different when you look at the klax. While I do have a klax I really didn't want to damage the back label to trace the traces and see if that resistor really need to be moved.

What purpose is the long yellow thin thing between the Rambo and PRG? I removed it and seen no change in any set-up. I could remove the 7432 again and jumper underneath but I will be left with a glitchy screen everywhere.
100_2030.JPG
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icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

Now I see what you are referring to w/the resistor under the 7432 I totally missed that it could go higher up. I'll try that.
icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

Yep that fixed it. Just moving that resistor up. Thanks. If I would have seen that I would have tried it lol. I thought the klax board had the resistor to the right instead.
lidnariq
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Joined: Sun Apr 13, 2008 11:12 am

Re: what's wrong with my Hard Drivin repro?

Post by lidnariq »

Any chance either of you would be willing to use a multimeter to document what the various jumper locations correspond to?
FrankWDoom
Posts: 260
Joined: Mon Jan 23, 2012 11:27 pm

Re: what's wrong with my Hard Drivin repro?

Post by FrankWDoom »

lidnariq wrote:Any chance either of you would be willing to use a multimeter to document what the various jumper locations correspond to?
I can put it on my list of to-do's. What specifically are you looking for?
icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

lidnariq wrote:Any chance either of you would be willing to use a multimeter to document what the various jumper locations correspond to?
You just want continuity correct. I can do that real quick. You want just the whites or the yellows as well?
lidnariq
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Joined: Sun Apr 13, 2008 11:12 am

Re: what's wrong with my Hard Drivin repro?

Post by lidnariq »

Yeah, just continuity from each side of the Rx things to what pins on the ROMs/cartridge connector/mapper IC.

I don't care about the yellow things—they should be capacitors (the cylinders) and a resistor array (long "SIP" thing)
icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

Ok had to pop out the resistors for accurate readings.

R1 goes to Rambo 19 and 20 front cart pin 31 all way to right and back cart pin all the way to the right, basically all the grounds.

R2 goes to Rambo 2

The middle section between R1 and R2 goes to prg hole 24.

R3 left side goes to chr 24, right side goes to cart pin 16 if I counted properly, from left to right, that being if you look at the top board, pin on the left between the gap in the pins.

R4 left side goes to chr 24 and right side goes to Rambo 21

Now for that resistor under the 7432 the left side goes to back side cart pin counting 8 from right to left which on my board is pin 22 counting from left to right. Right side goes to chr 22

Of course as you can see in the picture of the klax board they also coincide with 7432 pins 11 for right and 12 for left.
icemanxp300
Posts: 159
Joined: Thu May 14, 2015 6:17 pm

Re: what's wrong with my Hard Drivin repro?

Post by icemanxp300 »

Just curious it doesn't really look like a glitch but when I crash for game over the glass breaks with number and such in it before it goes to game over. Everything else looks fine, do you get the same?
lidnariq
Posts: 11429
Joined: Sun Apr 13, 2008 11:12 am

Re: what's wrong with my Hard Drivin repro?

Post by lidnariq »

Ok, to interpret:

R1 and R2 select whether PRG ROM pin 24 is PRG A16(R2) or ground(R1), in other words, whether this is a JEDEC 28-pin mask ROM/a 32-pin Nintendo mask ROM (R2) vs an ordinary ROM (R1).

R3 and R4 select whether CHR ROM pin 24 is CHR A16(R4) or PPU /RD(R3), i.e. the same meaning as above)

74'32 populated vs the jumper underneath is the same, controlling whether CHR ROM pin 22 is [PPU A13 OR PPU /RD](ic; above mask ROMs) or PPU A13(jumper; other ROMs)...

last two questions:
1- Where does R6 go? It looks like it would tie something to ground.
2- Where do the solder pads on the reverse next to the label "P28" go? (That should be PRG A17, but...)
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