TECH: Sega Turbo S's on the screen. Replace Z80...

Tombo

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A non collector friend was drooling over a Sega Turbo the other day so we went and picked it up last night. It comes up with S's on the screen and the LED's are randomizing.

From what I read on a few old Usenet posts, the CPU glob on the pcb is shot and the fix is burn unencrypted ROMS and pop in a z80 in the socket.

So I have read the fix is:


  1. Two Roms with a z80 or
  2. 6 roms with a z80a
My questions are:


  1. Will any z80 work? (z80, z80a, z80b, etc...)
  2. What type of blank eprom do I need to use? (2532, 2716, etc...)
  3. What roms do I actually replace?

Thanks in advance for any and all help.

-Tom
 
Solved the problem and fixed the game.

Found the answer at ionpool.

The three roms to replace are labeled epr-1363 epr-1364 and epr-1365 and are under the silver glob.

I used the images in the zip file and burned to three 2764's.

Used a z80 from a dead donor board.

-Tom
 
Sweet!

Next time if you are unsure of what CPU to use, check the MAME entries for it at http://maws.mameworld.info/maws to see what clock speed the CPU is running at.

This will help you determine which flavor of Z80 to use.

RJ
 
Sweet!

Next time if you are unsure of what CPU to use, check the MAME entries for it at http://maws.mameworld.info/maws to see what clock speed the CPU is running at.

This will help you determine which flavor of Z80 to use.

RJ

Yeah, that's assuming they're correct, which is not always true....
If you have to buy Z80's, just pick up Z80B and you can safely use them in any video game application that needs a Z80 (never seen one clocked higher than 6 MHz on a vid).
 
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