I'm trying to make MUSHA, and have been trying all day to get a 27c400 to program. No luck.
What chips did you use for 512kb games? I'm using AM27c400 chips.
Maybe the chips are bad, or probably just the programmer again.:unhappy:
Printable View
I'm trying to make MUSHA, and have been trying all day to get a 27c400 to program. No luck.
What chips did you use for 512kb games? I'm using AM27c400 chips.
Maybe the chips are bad, or probably just the programmer again.:unhappy:
Can't program it it, or it will not run? I never had troubles with 400's (I had trouble with every one else though). If you can't program it, try erasing it for a longer period of time. You do have a UV eraser, right?
Can't program them at all.
As soon as I try to program they just give me errors. I'll try erasing them for a longer time, I'll put them in my UV eraser for a few rounds later and try them again.
I made my first Genesis repro the other day using a 160, no problems. I even managed to program 322's without any hassle. The 400's are the only ones to give me troubles so far.
What kind of adapter are you using? Are you using the right socket on it?
I'm using the standard green 16bit Sivava adaptor. It has a 42 dip socket to the left and a 40 dip socket on the right. 160's and 322's have worked fine with it so far.
I have only tried them in the 42 pin socket up to press.
The 27c400 chips have to go in the smaller socket. I think I will make an adapter board for the Arduino Mega which sets on top like an Arduino Shield and will program these IC's. It will end up being cheaper than the Sivava nonsense and also be fully USB compatible. It will probably require an external power supply though because of the +12.5v VPP connections of UV-EPROMs. I'll also make it open source since I am not the strongest C++ programmer.
Tried them again today after giving them 3 rounds in the eraser yesterday and still they refuse to program.
popped them in the other socket and still nothing. They give me errors the instant I click program, I just cannot I understand it. All the dip settings are correct, everything is correct.:sa-frown:
I hate this programmer. Some chips program without any issues and others will not program ever.
My mistake, they do go in the same socket. I was looking at a non-Sivava adapter. In any case, I don't know what to tell you. Willem sucks for most, but is good for some.
I actually sat down this morning to start working on a new open source programmer based on the Arduino Mega and it's XMEM (Ext. memory Interface). I am designing a shield which will support all of the 8-bit eproms just like the Willem and will also support 16-bit eproms with the use of an adapter. It may or may not support the Willem adapters, but it WILL have a reliable power source to control VPP. It will have full USB compatibility but may be a year or more before it is useable. I don't have experience in PC-coding to get it working yet, but I will be working with a few people to help out.
Major update, I sat at my computer all my day off to get this far. It will accept 32-pin DIp and 32-pin PLCC eeproms and will be able to program them via the XMEM interface. There is no software as of yet and it does not yet support adapter or UV-EPROMs. These will come next and as you can see, I have started adding both.
http://i.imgur.com/vQERZyBl.png
http://i.imgur.com/xO4W3yYl.png
I have a problem. I wanted to make the Bad Apple Demo (which is 8MB) onto a cartridge. However, I was thinking to use a 74LS139 just like in SNES games, but obviously this won't work, or does it? Either way, if this works, how exactly would I connect the decoder? Or is there another way to do this? Help appreciated.
Yeah, you should be able to do that, but it will overlap the memory space reserved for the MegaCD or 32x. All that means is you cannot use them while using that cart.
I will draw a diagram for you later.
All you have to do is tap into the higher address bits on the cart edge which go to the 74ls139, then the outputs from the 139 go to the the control logic inputs (Chip Enable) of all of your ROMs.
Read the datasheet!
http://pdf1.alldatasheet.com/datashe...I/74LS139.html
A diagram for that would be awesome. I'm not planning to use the 32x or MegaCD with that anyway.
Hi and thanks for your guide.
I have a 2Mb Megadrive cartridge as donor. Can I use a 512k or 1024k EPROM on it ?
Regards
Yessir, you may.
Quote:
http://img28.imageshack.us/img28/9471/dsc00167bb.th.jpg
^notice that hole 1 is empty. That is because 27c400 chips have only 40 pins instead of 42. Place 512KB chips all the way to the right.
And here is the diagram for xIceMan. Take special note of the items within black boxes.
http://i.imgur.com/ERBbHB4l.png
Awesome. Thanks alot. Going to try this later!