[sebhc] Schematic

[Carroll Waddell]

Lee,
That sounds interesting, but how do you get an 8080 to address more than 
64K?
Carroll

(PS) I remember working on an old IBM system that used an 8085 processor 
and had 128K. I don't recall how they did it though.

Lee Hart wrote:

>Carroll Waddell wrote:
>  
>
>>Does anyone have an x-ray view from Heath of the H8-17 controller
>>board? I would like to try to clone that board.
>>    
>>
>
>I don't have it either, but wish I did.
>
>But, the board that I think would be better to clone would be the
>soft-sector controller (H8-37 I think). It supports far more disk
>formats, and even has the SCSI connector for a hard drive.
>
>  
>
>>Now that I have found a source for the H8 card connectors, I will be
>>making some hardware boards. If anyone is interested, the first one I
>>will make is a 64K memory card.
>>    
>>
>
>64k is awfully small; one single memory chip. Might I suggest you make
>it support (say) eight bytewide 28- or 32-pin devices, and have the
>jumper options and bank select logic to allow it to be populated with
>either RAMs or EPROMs, from 8k to 512k each. I already have a design
>done for another project which I can share if you like.
>  
>