Genesis ROM / Radica / Cartridge Slot Talk

JackFrost22 · Post by **JackFrost22** » Sun Dec 12, 2004 8:36 pm

they dont guess we are left in the dqark I will do what i can

SgtBowhack · Post by **SgtBowhack** » Mon Dec 13, 2004 4:46 am

Sorry about the "late" response- Japan time and US time isn't too compatible. Anyway, yes, I meant what I said. Super SF2 on the Genesis was at least 40 megabits. The SNES version was 32 though, I think. (Note, a website comparing the SNES and Genesis versions say the Genesis one is 40 and SNES 32, but don't take it as gospel). I think it was the only Genesis game to be above 32Mbit though.
Anyway, the ROM needs to be at least 24Mbit because it contains 6 4Mbit games, and I doubt they could crush it down to 16 very easily. It says on the Japanese one pictured on the Lik-sang website that it's 32 though.
Yeah, so you need 38+voltage+GND... are we positive that those are indeed all GND and VCC? I'd say to retrace them and make sure one more time, there may be a mistake in there.
Oh, and btw, the math adds up according to this:
1-ground
23-VCC (connected to 33)
32-ground
33-VCC (+3.27v)
Those are the pins we're fairly sure about now, right? segasonicfan says pin 1 is grounded *shrug* Is it possible you two are working with different region versions? *hopeful look*
To summarize, you need 38 pins + 2 for those other signals you mentioned plus the four above. Therefore, we have 44 pins needed and 44 pins are indeed what we end up with.

Post by **benheck** » Mon Dec 13, 2004 8:34 am

Yeah, but pin 1 on the Radica ROM looks like it doesn't connect to anything. Or was supposed to but doesn't.

Thoughts?

segasonicfan · Post by **segasonicfan** » Mon Dec 13, 2004 10:30 am

pin 1 is ground. I'll double check again when I get home, but I am quite sure. The ROM included with the Radica alsu uses pin 1 as ground so it's very unlikely that I'm wrong...but I'll check again...

And Ben, the best way to remove the white stuff is with an exacto knife-I got all the traces visable on my Radica now =) Just scrape away...sometimes it helps if you get it wet too.

I hope you can figure out the pinout...I would love to make this into a portable. And I'm pretty sure the lines I traces are correct, I've followed the traces very carefully. I'm also thinking of getting a schematic of the other ICs and the board and using the data lines from the schematic to figure out what the data lines are from the ROM...would that work?

-Segasonicfan

SgtBowhack · Post by **SgtBowhack** » Mon Dec 13, 2004 3:55 pm

Well, it looks as if one of you is wrong but frankly it doesn't matter much... the math adds up now, right? So now it is time to get to figuring out the pinout

I'd help but I'm pretty useless in such matters... especially since I'm in Japan, so the Sega Toys release here might not even be 100% the same as the Radica one (it does specifically say Japan on the ROM on Lik-sang's website). Not to mention I'm without my soldering iron here.

JackFrost22 · Post by **JackFrost22** » Mon Dec 13, 2004 4:26 pm

Are you mad how do you live

Cyberblade · Post by **Cyberblade** » Mon Dec 13, 2004 5:06 pm

Has anyone ever thought of trying to get inside information about these things? Perhaps contacting somebody who helped construct it. Sure you'll prolly get a bunch of crud about not taking it apart, but they've got their money so why should they care? I figure somebodies going to call me a moron, or someones going to say that takes all the fun out of it, but I'll say it anyways.

JackFrost22 · Post by **JackFrost22** » Mon Dec 13, 2004 5:09 pm

i probszbly could if IBM made it

MM007 · Post by **MM007** » Mon Dec 13, 2004 7:06 pm

segasonicfan wrote:pin 1 is ground. I'll double check again when I get home, but I am quite sure. The ROM included with the Radica alsu uses pin 1 as ground so it's very unlikely that I'm wrong...but I'll check again...

And Ben, the best way to remove the white stuff is with an exacto knife-I got all the traces visable on my Radica now =) Just scrape away...sometimes it helps if you get it wet too.

I hope you can figure out the pinout...I would love to make this into a portable. And I'm pretty sure the lines I traces are correct, I've followed the traces very carefully. I'm also thinking of getting a schematic of the other ICs and the board and using the data lines from the schematic to figure out what the data lines are from the ROM...would that work?

-Segasonicfan

can you post a pic and maybe even a make of the chip? maybe it is a common kind of ROM that isn't specific to the Radica, if we're lucky.

I find it unlikely that they made the whole thing in-house, esp since 32K ROM chips are readily available elsewhere. It may be an existing one.

JackFrost22 · Post by **JackFrost22** » Mon Dec 13, 2004 8:26 pm

Yeah its probably a standered prom or rom

segasonicfan1 · Post by **segasonicfan1** » Tue Dec 14, 2004 12:37 am

Hrmm..I was wrong. I checked and pin 1 is N.C. not ground. However, from the looks of things, pin 13 is grounded. I can't tell for sure since that's one of my traces that got ripped off, but it can't be connected to anything else. So that's ground or N.C. as well.

-Segasonicfan

segasonicfan · Post by **segasonicfan** » Tue Dec 14, 2004 11:48 am

Well, I found out some (possibly helpful) info. I wanted to see how to obtain audio R and L from the system so I followed the audio output to the LM358 chip. This does exactly as I expected-it amplifies and combines the two audio lines. Here's a full pinout and info datasheet on the chip:

http://www.digchip.com/members/parts/lm ... 8527173498
You need to register to Dighip.com for the diagram...it's free though, and a great way to search for datasheets of obscure ICs.

I also tried to find some info on the LS32 Texas Instruments chips...I came up with very little as these are suprisingly hard to find information for. However, I did come up with an NES Pinout for it here:

http://www.tripoint.org/kevtris/nes/nestuff2.txt

The Texas Instruments Schematic can be found here:
http://focus.ti.com/lit/ds/symlink/sn74ls32.pdf

I also found some info here:
http://www.cs.toronto.edu/~hehner/csc258/pinout.pdf
http://engineering.dartmouth.edu/~engs0 ... 74ls32.pdf
http://www.site.uottawa.ca/~melkadri/ta ... series.pdf

This should help out anyone that knows software for finding the pinout. Hopefully someone can use this info from the LS32 chips and trace it back to the ROM to find what and where the data lines are.

The last IC on the board is the HC174. Here is the official Texas Instruments Datasheet for any and all info on the chip:

http://www.unicornelectronics.com/ftp/D ... -hc174.pdf

HK-47 · Post by **HK-47** » Tue Dec 14, 2004 2:32 pm

If you dont want to register use www.bugmenot.com . Heres a name and password for the first link:
dig3510f
c0du5ckx

segasonicfan · Post by **segasonicfan** » Tue Dec 14, 2004 4:38 pm

Okay, I have some spare time so I'm also going to give a pinout list of the ROM chip from the chip to the corresponding LS32/HC174 circuits. Here's what I came up with:

6-Pin 14 of HC174
7-Pin 13 of HC174
8-Pin 11 of HC174
34-Pin 6 of LS32 (top one)
35-Pin 3 of LS32 (top one)

If anyone thinks this information is helpful I can desolder the chips to find the full pinouts for them...just let me know.

Basically I'm just trying to do the busy work to help the software people figure this thing out

-Segasonicfan

JackFrost22 · Post by **JackFrost22** » Tue Dec 14, 2004 4:47 pm

Yeah thaks fir tge pinout