Thread: Spectrum advice
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Old 3rd Jan 2020, 1:12 am   #12
arjoll's Avatar
Join Date: May 2006
Location: Invercargill, New Zealand
Posts: 2,846
Default Re: Spectrum advice

Originally Posted by RogerEvans View Post
The 4116 DRAM chips have three power supply lines, all of which have to be correct. Pin 16 is ground, pin 9 should be at +5V, pin 8 at -5V and pin 1 at +12V.
I'm seeing -5V and pin 1 and +12V at pin 8, but looking online that appears to be correct.

I think I'll recap anyway, and do a bit more work in the weekend to see if I can work out anything else.

It's using a 6C001E-5 ULA which is apparently not particularly common, and has an upside-down daughterboard with a 74LS157 installed in place of IC26.
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