QBERT: 7489 ram vs. 74S189 ram

Robotron Jon

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Are 7489 ram and 74S189 ram the same thing?

I noticed in the Qbert manual that this is referenced as 7489 for G13, G14 and G15 and as 74S189 for H1-H4. Are these different RAMs? I called my parts souce and they only had 7489 and they did not know if they are the same thing. Seems like they are both 64 bit rams.

Thanks.
 
The S means that the clamping diodes are schottky. Unlikely to cause a problem, but I'd recommend sticking with an exact replacement just in case.
 
The S means that the clamping diodes are schottky. Unlikely to cause a problem, but I'd recommend sticking with an exact replacement just in case.

I guess I better check my board and see what's really installed. I read through some old threads and apparently the spec sheets on some games are not totally accurate vs. final manufacturing. I guess the board is the final word.

Thanks.
 
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When I said they are the same I meant you can sub them for each other in most cases. Its kinda like the 4801's in row E on qbert. You can use a standard 6116 on those. There are a couple low power 6116 in the top row on a qbert that should only be replaced with low power rams.
It is true that alot of boards were built with different chips than specified on the schematics.
 
When I said they are the same I meant you can sub them for each other in most cases. Its kinda like the 4801's in row E on qbert. You can use a standard 6116 on those. There are a couple low power 6116 in the top row on a qbert that should only be replaced with low power rams.
It is true that alot of boards were built with different chips than specified on the schematics.

Thanks for the information, I appreciate it.
 
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