Well apparently my problem wasn't real. It's working now.. Must have been a poor contact the first time I plugged it in. Time for romset number two testing I guess. Although I will try the original bios version first.
The description is in the first message of this thread, you need to build a special version of the program rom that includes the special bios from a stand-alone game.With the QB DDP, its the same romset across the m27c322, no change? and just the QB on the U5 GAL + JP1? = bypass stock bios?
Yes, hold the test button for ~1s.Also do any of the 3 cave carts offer any bios settings or options etc via test or service?
There's room to make a case with sockets but I can't tell you if the existing one someone designed has enough roomQuestion: I've seen posts go back and forth asking this but I haven't seen a picture of anyone actually doing this. Can the EPROMs be socketed with the 3d printed cases or is there still a clearance issue and the EPROMs still need to be soldered? I'm about to assemble my first one (friend gave me a PCB set) and would prefer socketed but will solder if it's the only way. Thanks in advance.
Thanks for the quick reply. Alright, I'll have to see about posting photos of the shell I printed out and see if the sockets work or not so others will have a solid reference in the future.There's room to make a case with sockets but I can't tell you if the existing one someone designed has enough room
Thanks for confirming!Yep. I've used GAL16VD on mine
https://www.arcade-projects.com/thr...ssembly-and-troubleshooting.10015/post-317834
Here's the gals I have installed
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PGM carts and slots can be very picky if the contacts aren't clean. I had to swab down my freshly assembled cart edges on mine, and found I had not made mistakes when it just worked then.I've built a DDP set, but I'm having difficulties getting it to boot. Most of the time it just goes straight to the test menu, but sometimes I get garbled pink graphics. My question is: is there a rule-of-thumb way of knowing if the files need to be byte-swapped or not? I suspect maybe I didn't byte-swap the files when I was supposed to.
I see in the early posts in this thread that the DDP header (paraphrasing) "should be garbled," but to facilitate that in my EEPROM burner software (using a TL866ii), I actually had to byte-swap the file myself. Does that then hold true for the remaining EEPROMs? I know the GALs I'm using contain resistors so I don't think the three additional resistors are necessary. Also, is it the case that, if everything in the "blue square" region (P1, GALs, etc) is installed properly, the game will at least attempt to boot? That'd be a great help for drilling down into the problem. Thanks!
Yeah, I've done a lot of cleaning of both the slot and the boards. I do have an OEM cart for testing the system and that boots without controversy, reliably, so I think the contacts are probably okay? Probably bears doing again though.PGM carts and slots can be very picky if the contacts aren't clean. I had to swab down my freshly assembled cart edges on mine, and found I had not made mistakes when it just worked then.
Mine turned out to be the Fluffy PCB needing a reflow cause the ground plane is so big on it that my iron wasn't hot enough to make some solder flow and caused a cold joint in some places. Give that a shot if the cleaning doesn't work.I've built a DDP set, but I'm having difficulties getting it to boot. Most of the time it just goes straight to the test menu, but sometimes I get garbled pink graphics. My question is: is there a rule-of-thumb way of knowing if the files need to be byte-swapped or not? I suspect maybe I didn't byte-swap the files when I was supposed to.
I see in the early posts in this thread that the DDP header (paraphrasing) "should be garbled," but to facilitate that in my EEPROM burner software (using a TL866ii), I actually had to byte-swap the file myself. Does that then hold true for the remaining EEPROMs? I know the GALs I'm using contain resistors so I don't think the three additional resistors are necessary. Also, is it the case that, if everything in the "blue square" region (P1, GALs, etc) is installed properly, the game will at least attempt to boot? That'd be a great help for drilling down into the problem. Thanks!
Which GAL16V8 are you using? It looks like some don't have pull-up on their inputs, so they'll be unstable without external pull-ups.Yeah, I've done a lot of cleaning of both the slot and the boards. I do have an OEM cart for testing the system and that boots without controversy, reliably, so I think the contacts are probably okay? Probably bears doing again though.
This is hard to answer. Generally: The EPROM is 16 bit, and the cpu reads them like that.I've built a DDP set, but I'm having difficulties getting it to boot. Most of the time it just goes straight to the test menu, but sometimes I get garbled pink graphics. My question is: is there a rule-of-thumb way of knowing if the files need to be byte-swapped or not? I suspect maybe I didn't byte-swap the files when I was supposed to.
I see in the early posts in this thread that the DDP header (paraphrasing) "should be garbled," but to facilitate that in my EEPROM burner software (using a TL866ii), I actually had to byte-swap the file myself. Does that then hold true for the remaining EEPROMs? I know the GALs I'm using contain resistors so I don't think the three additional resistors are necessary. Also, is it the case that, if everything in the "blue square" region (P1, GALs, etc) is installed properly, the game will at least attempt to boot? That'd be a great help for drilling down into the problem. Thanks!