Donkey Kong Woes

ckasek

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*sigh* I have a DK board that had been converted to Herbie at the Olympics. I got a DK ROM set from another member here, swapped them in and installed a HSS kit. Gamed booted up, played a few games (i suck at DK!), and I shut it down.

Came back a few hours later, turn on the power, i get the normal startup sound but nothing on the screen, and the game isn't playing blind. I try restarting without the HSSK, and I get the garbage screen below.

I swapped back to the herbie ROM set, and have the same exact issue - so seems to be a problem with the board, not the roms. Anyone have any ideas?

nHpoR.jpg
 
I bet your Z80 isn't completely seated. Try that first because it's so easy to do.
 
no luck with that, still the same results:

herbie daughterboard fully seated, junk on screen.
DK z80 fully seated, junk on screen.
DK HSSK fully seated, nothing on screen.
 
Hmm, first let's be sure you're actually using a Z80A CPU. I included a spare 8035 MPU with your chipset, since I had one. That is of course, the music processor, and not interchangeable with the Z80A CPU. Also, the CPU the Herbie kit used is not a Z80A (although I mentioned this before).

Second, if you're sure everything is seated properly and you are indeed using the Z80A CPU - it's entirely possible that your HSS kit (daughtercard) damaged the receiving pins on the CPU socket. The thick pins on those can stretch out, crack, and generally destroy a CPU socket. Examine it closely for cracks and make sure the pins make good contact.

Third, I suppose it's possible that you installed the CPU the wrong way during all the swapping and killed it. Another Z80A CPU on hand would determine that.

Lastly, garbage screens are typically indicative of a low power feed. While you say you just recently played DK with the HSS kit and presumably this PSU, it's possible that your PSU is weak and not providing enough +5V for the game to boot. Test with a multimeter, and if necessary, disassemble the PSU and locate the +5V adjustment pot (evidently there is one in the "gold box," I've just never used it myself).

And as a long shot, make sure your PCB interconnect ribbon cables are all seated fully. If you separated the boards to seat all the chips, you may have not plugged one in fully, bent a pin in one, or introduced some debris into the connector that is preventing throughput.
 
well, I got Herbie back up and running again - i guess even the 2nd time around I didn't have the daughtercard seated good. third time is a charm.

I ordered the HSSKit and the z80 from mikes arcade, but I ordered this Z80 - http://www.mikesarcade.com/cgi-bin/store.pl?sku=Z80CPU

Sounds like I got the wrong one...weird though that it booted up and played the first time around. When I pulled the HSSK, i used the chip you included and left the Z80 in the HSSK. I guess I assumed you tossed in a z80 since you knew i didn't have one....that's what I get for assuming. That explains the garbage on the screen!

So, should I try booting it without the HSSK using the z80 from mikes, or should I just order a z80a and leave it be until I get it? Will using the z80 i have damage anything?
 
The Z80 from Mike's is correct. Plug it in and it should be fine (D780C was NEC's code for the Z80A).

Sounds to me like it's all been card seating issues. If you reinstall the HSS kit and FIRMLY seat it, everything should be peachy. You probably just had it pressed in *just* enough for it to play for awhile, and then temperature change or whatever made it slide back out far enough to not boot later. You really have to lean into it to install the HSS daughtercard properly. It's recommended that you separate the 2 PCBs, lay the CPU board on a towel or thick cardboard, and then proceed with the install. So you get enough leverage to seat it fully without cracking your PCB (yes, you have to push almost that hard).

Don't sweat it, it happens to just about everyone when they first buy these daughtercards :)
 
you hit the nail on the head. Swapped everything back to DK, and made sure to insert the HSSK firmly. Could definitely tell the difference between now and the last two times I seated it, was down in the socket a bit further. Back up and running again. Thanks for all the help.
 
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