Making an Earthbound NES cart

[chaoticjelly]

I want to make a NES Earthbound cartridge (a PAL one) and I was wondering if anyones made one before, ive pm'ed Leonk who apparently owns nesreproductions.com, twice, but unfortunately he doesnt seem to reply (or hes having problems with his pms)

So basically I attempted to make one tonight.. and it doesnt work

I prepared the files (256K CHR and 256K PRG) as per the instructions on romlab

The cartridge I have as a donor is "Shadowgate", the PCB is marked "NES-TKROM-02"

I found the following file on the internet :

http://nesdev.parodius.com/NES%20EPROM%20Conversions.txt

It has various instructions, and I followed the instructions marked "TKROM & TSROM (mapper 4):" ?

The instructions are a bit unclear - it says to either lift the pins of the EPROM, or cut some tracks. So what I did was cut the tracks it says, on both sides of the board (where applicable) and then I soldered the wires to connect the pins & holes as per the instructions.

Now I just get either a solid blue screen, or a flashing blue screen on and off. The NES is working perfectly it has a new connector, so thats not the problem.

I checked that all the tracks were cut correctly with a multimeter...

Does anyone have any suggestions?

Thanks!

Many thanks,
James

[chaoticjelly]

I want to make a NES Earthbound cartridge (a PAL one) and I was wondering if anyones made one before, ive pm'ed Leonk who apparently owns nesreproductions.com, twice, but unfortunately he doesnt seem to reply (or hes having problems with his pms)

So basically I attempted to make one tonight.. and it doesnt work

I prepared the files (256K CHR and 256K PRG) as per the instructions on romlab

The cartridge I have as a donor is "Shadowgate", the PCB is marked "NES-TKROM-02"

I found the following file on the internet :

http://nesdev.parodius.com/NES%20EPROM%20Conversions.txt

It has various instructions, and I followed the instructions marked "TKROM & TSROM (mapper 4):" ?

The instructions are a bit unclear - it says to either lift the pins of the EPROM, or cut some tracks. So what I did was cut the tracks it says, on both sides of the board (where applicable) and then I soldered the wires to connect the pins & holes as per the instructions.

Now I just get either a solid blue screen, or a flashing blue screen on and off. The NES is working perfectly it has a new connector, so thats not the problem.

I checked that all the tracks were cut correctly with a multimeter...

Does anyone have any suggestions?

Thanks!

Many thanks,
James

I've figured something out now.. I was wiring the rerouting wires to the actual pins of the eprom, NOT the holes which are on the other side of the cut track D'oh, it was not very clear that was what should be done.. so this is probably why its not working.

I will redo this tomorrow and post whether it works or not.. also I checked out a datasheet, and it seems there is a possible error in the guide..

[Necrosaro420]

Take pin 24 and tie it to pin 16 (of the prg chip) and that should fix your problem.

[chaoticjelly]

Ive done that, its still not working..

There is a hole on PRG and a pin on CHR, which the guide has you tieing a wire to, and then the other end of the wire goes to a pin of the EPROM, but the two holes, are already connected to EPROM pins e.g programming pin, does this not matter? The guide doesnt say to cut those tracks!

:roll:

[chaoticjelly]

Ok I took another cart and wired it up by lifting the legs, I get music, and then a spinning earth, which I suppose is the title screen, but the rest of the graphics arent there?

Does this mean that there is something wrong with the CHR eprom? Is it a bad burn? Did I connect something wrong or..?

On the CHR EPROM there are two legs unconnected.. should these be connected to something?

[chaoticjelly]

Awesome, I missed lifting a leg, so I just cut it, and now the carts working perfectly 8-)