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Stuie78

Understanding a Barcrest MPU4 program card

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Good morning all. 

 

Just a post to expand my knowledge...I’d love to hear your answers but am also happy to be corrected on anything that I think is right but isn’t. 

 

Barcrest/BWB MPU4 program cards. 

 

As I understand it...on a Barcrest game card there are 4 EPROMs. 1 for the game play, stakes, jackpot etc, 2 for sound & 1 skinny one.
 

1. What’s the skinny one?

2. I’ve read the term chr...what’s that stand for?

The other chips are permanent chips so I don’t need to know what they are or what they do. 

The Barcrest “security chip” (I don’t know what that is or where it is on the card). 

3. Is that security chip specific to the game or to the machine? I mean, for example, can any Andy Capp program card go in any Andy Capp machine or is it 1 card, 1 machine? 

4. Depending on the answer to that...to change the game stake & jackpot, do I replace the program card with new EPROMs on or do I replace the EPROMs on the current game card? And do I replace/burn all 4 EPROMs or just the game card?

 

5. Are other mpu’s as restrictive? It looks like they’re not as the EPROMs either go directly on to the MPU or the game cards are a lot more basic  

 

Thanks very much

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Posted (edited)

Skinny card I’m not sure about, there are at least 5 revisions of the MPU4 cards 

photos below

issue 1: dated 1983 is a mod 0/1/2 card used in ealier machines and has 1 to 3 roms, and is non sampled and has 1 pic chip which is matched to the eprom, you need to keep PIC chip safe as its essentially unreplacable 

issue 2 (reversion semi sample) I don’t know much about, it’s a transition card with a PIC chip and game Roms that are used in semi sampled/synth machines, early 90s for the most part 

Sample Program 1 - 1992 Small T has 2 security chips, 1 is matched to the rom and one is sound related, change both if you are swapping Rome over to be on the safe side. This is fully sampled sound, 2 sound roms, and 1 game

Sample Program 2 - 1994 a slightly bigger T revision, with the same function of the 1992 one, backwards compatible, has 3 security chips, but only 1 rom matching (chr)

Sample Program 3 - Big T and multiple security chips, features 4 security chips, up to 4 sound roms and 2 game roms, only 1 security chip is matched to the game Rom as far as I’m aware

Video MPU4 - A game card with 1 or 2 roms with no security chips that plugs into the MPU4 and is connected to the video system

Edited by -Crest-
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CHR stands for chastised chip

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Posted (edited)

I’m 99% sure the CHR is IC8 on 1994 card, please correct me If I’m incorrect

836103A6-742B-4B9E-B0A5-B1F014E1B5FE.jpeg

Edited by -Crest-
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Note: half of the card is missing on mine not really sure why lol, usually not like that 

DE773423-6BCE-4D61-925B-22DFB5FD034B.png

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Also note: make sure you know the orientation of the chip, never put it in the wrong way. 

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Crest, WOW that is some incredibly good information. I’ve got a couple of more specific questions but I’ll need to look at my boards when I get home. Thank you mate 💪🏽👍🏽

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Oh ya and to change the jackpot or stake yes usally you need Roms, are possibly even a different pic chip. Some machines are switchable but most aren’t, an exception would be empire and late MDMs on MPU4 and later club machine they usally are switchable without replacing roms.

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Question 5 I’m unsure about, all Techs are different. A big drawback on MPU4 is the CHR imo, but nothin you do about it unfortunately 

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So here are my Andy Capp program cards. Looks like they’re 1992 sampled sound. Didn’t know there were so many. 
 

the first photo shows the card that works. Unfortunately it’s the wrong JP. The next photo shows my spare card with the correct JP. It doesn’t seem to want to work in my machine. It came out of a working Andy Capp so I don’t understand the compatibility issues. Perhaps it’s just corrupt? Or is it something to do with the CHR?
 

Can I simply transfer over 1 or more chips to the card that I know works? If so, which chips? A - E. 

 

Thank you

690CDDB0-E7A1-4358-8718-48E3963C88D3.jpeg

007716A3-BE4F-4C7E-9DE7-DAAC84647758.jpeg

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The other card could just be broke, number of reading for it or roms corrupted etc, yes you can swap roms over, just be careful. With a bit of luck you might have a spare CHR there.. be sure not to damage the roms with static 

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You can switch over any of the chips 

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I switch just “D” which gave a bad character alarm so switched “E” too which solved it. Andy Capp up & running on the correct jackpot. 
 

Thank you mate. That information is so useful 👌🏽

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Decent mate yes it seems the CHR (E) is matched to your game rom, if the jackpot or stake is different sometimes the chastiser is to 

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