Radica Mask Rom "jumper" thread

[nubie]

I just built a Radica portable http://forums.benheck.com/viewtopic.php?t=23215 (my first . Yay! ), and I was curious about the mask rom chip:


Full Size (click download): http://picasaweb.google.com/nubie07/RAD ... 1455302322

This is a Legends II unit (Sonic 2, ECCO, Columns, Ooze, Gain Ground, Alex Kidd).

I was wondering if the mask roms on all (or some) of these Radica chips are the same, and the "content" is chosen with the solder blobs. IE the Legends one and two roms are the same and the factory bridges the gap to get the correct games.

I have been looking for pictures of the Rom, but so far no luck. I threw away my Legends I unit when some mice got into the box holding it (very gross), so I can't compare the two.

I am going to test the pads and see if any are tied to voltage or ground, but if anyone has a picture of theirs (or can check and draw on my picture to show us where the solder is).

I could just clean off the solder and start experimenting, but I just built the portable and I don't want to ruin it just yet.

Thoughts?

EDIT: I notice now that the stickers on these chips say 32 or 32M (IE 4 megabytes, IE only enough to hold the games they are supposed to come with).

If anyone has any info on this, I would love to hear it. So far I have seen 3 different mask rom boards, mine (NTSC), and a couple PAL versions.

[sam_thornley]

Hmmm, interesting...i think this has got to be true because this would save radica manufacturing costs and all.

Having the same mask rom with all versions of the radica rom images all ready contained is quite likely. So on the production line of PAL/NTSC radicas they attach the mask rom board, then configure the jumpers as to what version the radica will be sold as Ver1, Ver2 or even the two players ones with street fighter 2 ect.

But i belive some of the mask rom boards don't have this feature because one of my radica version 2's has "PAL /R2" on the lable. Anyway i'll see what i can do, i'm currently looking in to this also.

[sam_thornley]

Well some bad news After some heavy experimentation it turns out that all those jumpers do is set write protection for the ROM chip its self. The ROM must be flashed some how at the factory, then the jumpers are set so that its not erased by turning the unit on and off repeatedly. (as i found out). Now i have a semi dead radica, because some of the games don't work they just freeze or the radica restarts. My mask rom is now corrupt and what makes things worse is that its the radica i use in my game block thats gone corrupt.

It might be still posable but i may have just joint up the wrong pins that may have caused this to happen. I would'nt bother and just add a cart slot. I have no chioce now but to add a cart slot or get a new one for my game block.

Any one else had any look?