help! point blank pcb eprom

PCB problems and fixes
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moto773
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help! point blank pcb eprom

Post by moto773 »

can someone help me please? i just brought this pcb for my machine and the ebay user haven't wrap it well and this eprom came out.. and i dont know now is position..





Thanks!

ps: anyone have the pcb manual? so i can plug it in well?
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nem
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Re: help! point blank pcb eprom

Post by nem »

That's interesting. It's for the sounds samples I think. Usually there should be a regular mask rom. It's possible your chip is undumped.

You can't check the pictures from the auction? If there are none, can you take a picture of the whole board?
moto773
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Re: help! point blank pcb eprom

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nem
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Re: help! point blank pcb eprom

Post by nem »

Ahh, it's a Point Blank 2. Well, I can at least tell you where the chip goes on the socket.
moto773 wrote: April 22nd, 2020, 1:01 pmcan someone help me please? i just brought this pcb for my machine and the ebay user haven't wrap it well and this eprom came out.. and i dont know now is position..

So in the pic above, the chip bottom should align with the bottom of the socket, so the top 6 receptacles (3 per side) of the socket will be empty.

As for how it should be oriented, if you have a multimeter you could look for common ground on both the PCB and the chip.
moto773
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Re: help! point blank pcb eprom

Post by moto773 »

yes and that's what i need to know... where and how the chip it will go to the socket.
yes i saw that the last 3 receptables/legs are not use by the dust it have on them..
how to see that? can you explain me please?
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nem
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Re: help! point blank pcb eprom

Post by nem »

Put your multimeter on continuity mode / diode test. Put one meter lead on ground on the edge connector, then go through all the receptables. Make a note which have continuity (which receptacles supply ground).

As for the chip, can you take a pic of the underside?
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