SMS not booting correctly. (Blank Screen)..

[knightkrawler]

Here are the pics via ImageShack...

http://imageshack.us/photo/my-images/838/sms1.jpg/
http://imageshack.us/photo/my-images/195/sms2jc.jpg/
http://imageshack.us/photo/my-images/841/sms3.jpg/
http://imageshack.us/photo/my-images/36/sms4.jpg/
http://imageshack.us/photo/my-images/857/sms5.jpg/
http://imageshack.us/photo/my-images/803/sms6.jpg/

Let me know which is the bios chip and i'll see what I can do..
Thanks!

[Ace_1]

Is it possible to assume the 315-5124 (64 Pin IC) is the bios and pin 20 is the one to disconnect? I worry about the word assume thou, eg. ass/u/me .

That would be a major mistake. The BIOS is the MPR-10052 chip. You need to disconnect pin 20 on that chip, cut the trace linking pin 13 of the cartridge slot(and card slot if you have any card games) to the Sega 315-5216(I suggest cutting it as close to the cartridge slot or 315-5216 as possible, depending on which is easier for you) then solder a wire from pin 39 of the 315-5216 to pin 13 of the cartridge slot.

[knightkrawler]

Ok I may try the cutting but don't really want to but then again what do I have to loose... Another thought I had was to open up the Hang On/Safari Hunt and noticed the chip to be a
28 Pin MPR-10137. Can I not try replacing this chip with the MRP-10052 or is this just crazy talk?

Thanks!

[Haunted360]

You don't want to break the trace.

Cut the pin so it does not touch and complete the circuit. So that you can bend it back and add some solder to re-connect it if it fails...

[Ace_1]

Ok I may try the cutting but don't really want to but then again what do I have to loose... Another thought I had was to open up the Hang On/Safari Hunt and noticed the chip to be a
28 Pin MPR-10137. Can I not try replacing this chip with the MRP-10052 or is this just crazy talk?

Thanks!

Sorry for the late response, but I don't think it would be entirely possible to do that without making a mess of your Master System. Ideally, you should just bypass the BIOS.

[Harlequin]

I have to ressurect old dead threads when it's about the Master System.

The skinny on games on board SMS 1 - the earliest models (I believe they were the earliest) had a boot screen that basically told you to turn off the machine and insert a cart or card and turn it back on again. You could press a series of buttons (something complicated like Down and button 1+2) and it would boot up a built in game called Snail Trail. This was the first console I ever owned.

Later versions of the SMS (which i got when the warranty replacement took too long) included Hang on/Safari hunt as a built in game instead of as an included Cart. I'm not sure how much money this saved Sega, but that's the route they took. Good for advertising to Grandma/Grandpa too "Your grand kids don't even NEED a cartrdige to play, unlike Nintendo" which is totally awesome and correct, especially if you only want them to play one of these two games forever. And Hang on is one of those awesome games that never ends either. Sweet!

the SMS 2 included Alex Kidd in Miracle World.

[knightkrawler]

Is there anyway to get these chips to restore the onboard game when they've become corrupt?

Thanks!

[knightkrawler]

Well I tried the modifications and still get nothing but a black screen when powered up. Dunno what else to try.. I don't want to throw this thing out but then again I'm starting to sound like a hoarder!!!

Any other suggestions?

Thanks in advance!!!

Is it possible to assume the 315-5124 (64 Pin IC) is the bios and pin 20 is the one to disconnect? I worry about the word assume thou, eg. ass/u/me .

That would be a major mistake. The BIOS is the MPR-10052 chip. You need to disconnect pin 20 on that chip, cut the trace linking pin 13 of the cartridge slot(and card slot if you have any card games) to the Sega 315-5216(I suggest cutting it as close to the cartridge slot or 315-5216 as possible, depending on which is easier for you) then solder a wire from pin 39 of the 315-5216 to pin 13 of the cartridge slot.

[Ace_1]

I found that mod to be a waste of time. I tried it on my Sega Master System on which I've added S-Video and a PAL/NTSC switch, and I can only get the console to boot a game by first getting a card-based game to boot. Then, it boots everything I throw at it, but the system becomes insanely unstable within a few seconds of gameplay. I think you need to cut the trace leading to pin 13 of the cartridge slot, card slot AND expansion slot, then link up those pins to pin 1 of the 315-5216. If that fails to work, either the 315-5124 is dead or the Z80 is dead.