PC Motherboard Flash Method
First of all you have to find a motherboard that can support 512k flash chips, if the one you have has got a 256k chip on it, it probably can support 512k.
The motherboard will have to have a
32 pin flash DIP chip. The small square BIOS chips (PLCC) are not really suitable - you can get an adaptor, but it will
cost more than an old motherboard.
The motherboard also has to have the option "System Bios Cacheable" or similar in the BIOS menu. This is a pretty standard
feature on motherboards. This option must be enabled. What this does is copy the BIOS program to RAM, so you can take out the
BIOS chip whilst the PC is running without damaging anything.
Also the motherboard needs some RAM, and you can just use a floppy drive with a bootdisk containing the flash software and the game file on it. What I do is connect a CD-ROM
drive, and have a bootable cd in it, so ALL the roms can fit on it. Note: Older boards might not be able to boot from cd-rom.
You can also have an emulator on the cd to try games out before flashing.
Do the following with your motherboard NOT powered up (best to do it before you connect it to anything)
On your motherboard, remove the BIOS chip from the socket, and put the 32 pin ZIF socket onto the BIOS socket. This allows you to replace chips easily. Now
put the BIOS chip onto the ZIF socket. Take note of which way round the BIOS chip is, the flash chip MUST go in the same way
You will have to create a bootdisk (on another machine) and add the uniflash utility and the game rom.
Ok, you now have everything set up to flash a game onto your 29f040 flash eprom. You will have to make sure have you pc setup to boot from floppy (or cd-rom) in the BIOS. Boot the computer, and
when it stops at the prompt, take the BIOS chip out and replace it with the 29f040 chip. With Uniflash, type uniflash -expert and get into the expert menu and use the option FLASH BIOS INCLUDING BOOTBLOCK,
then enter the name of the rom you want to flash.
Put the chip into your flash cart (see cart section), and you're away!! You can do more than one chip in a session, just put another 29f040 chip into the ZIF socket and run the flash program again.
Remember, to boot the machine, you have to have the original BIOS chip inserted.