Author Topic: Replacement Z80A CPU  (Read 713 times)

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Offline darkhalf

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Replacement Z80A CPU
« on: 16:58, 18 May 21 »
Unfortunately my recently aquired CPC464 will did not power on. Sometimes screen would scroll random patterns and then stop.


I swapped the Z80A over (from the other CPC464) and all came to life fortunately. Was hoping it wasn't one of the ASIC Amstrad parts!


So now I'm in the hunt for another Z80A. Do you need to use the Zilog ones or can the Sharp ones be used?

https://www.ebay.com.au/itm/372272867554


Does anyone know of a reliable source for these?


I'm in Australia, and freight is a nightmare 60GBP just to get the 464 here due from the UK. Many ebay sellers have complaints of counterfeit chips. I've seen this first hand with CRTC chips. Had one good one, and one fake


thanks
Matt
« Last Edit: 07:33, 19 May 21 by darkhalf »
CPC6128, 2xCPC464, C64, A500

Offline TotO

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Re: Replacement Z80A CPU
« Reply #1 on: 17:05, 18 May 21 »
Use NMOS Z80 CPU to be fully compatible with CPC programs like Z0840004PSC.
I don't know about if the Sharp Z80 are NMOS or CMOS...
« Last Edit: 17:08, 18 May 21 by TotO »
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Offline darkhalf

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Re: Replacement Z80A CPU
« Reply #2 on: 00:36, 19 May 21 »
Okay thanks will dig further


Part number on working 464: MOSTEK MK3860N-4
Dead 464 and my working 6128: Zilog Z8400A PS (380A)


Edit: CPC service manual has IC111 as Z84400 APS
« Last Edit: 00:39, 19 May 21 by darkhalf »
CPC6128, 2xCPC464, C64, A500

Offline RetroCPC

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Re: Replacement Z80A CPU
« Reply #3 on: 16:38, 19 May 21 »
Are you sure the Mostek part number is not MOSTEK MK3880N-4 ?

Anyway, this is a better link for a NMOS Z80A:-

https://www.ebay.com/itm/402782080514?hash=item5dc7aece02:g:-Y8AAOSwSddgbVrT

With ordering from China, you always have the risk of fake parts but the cost of this part its not going to break the bank...

Offline TotO

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Re: Replacement Z80A CPU
« Reply #4 on: 17:22, 19 May 21 »
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Offline Bryce

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Re: Replacement Z80A CPU
« Reply #5 on: 17:36, 19 May 21 »
I've bought parts from them in the past too and they were always good. Now if I could just convince them to stop using that non-ESD safe pink foam they use, they would make it higher on my favourites list!

Bryce.