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XT-CF into an AT 16 bit bus?

Twospruces

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Given XT-CF and the like are 8 bit - is it possible to do something similar for 16 bit?

I guess this is a bit of a challenge. I assume you would have to redesign the hardware to work for 16 bit bus, and that change would drive some changes to the flashing utility.
The CF card itself looks to support 16 bit directly.

Any insights appreciated. thanks.
 

krebizfan

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There were 16-bit ISA IDE cards about 30 years ago which worked with CF cards through an adapter. I think there were even front plate mountings to let one change the card without opening the case.
 

Twospruces

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as I read more on this, I guess this just *works* - provided it can keep up with the CPU. The so called "AT bus" was backwards compatible to the "XT Bus". So, I think this means an XF-CF will work as is, albeit in 8 bit mode. yah?
 

Chuck(G)

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Probably will work fine--weren't folks putting the XTIDE cards into PS/2 Model 30s? You may get far better performance by getting a plain old 16-bit ISA IDE card and an adapter, however.
 

Eudimorphodon

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I guess the question that sort of comes up if you have a 16 bit bus is, well, do you want an XT-CF at all? You should be able to implement a full 16 bit IDE port with approximately the same amount of address decoding. (If the machine you're trying to stick it into already has some kind of 16 bit AT hard drive controller at the standard addresses you could use the secondary ones.) Then just figure out a way to jam a ROM with the XTIDE BIOS configured appropriately into the machine.
 

Twospruces

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This new machine to me, Sharp PC 6220 has a Connor 20MB HDD which is working, but I think it probably wont last.

I have a spare xt-cf card for my zenith Z171.

I would like to simply wire in thi xt-cf and gain a compact flash port with minimum efforts.

There isn't an actual isa port, but the signals all exist on an expansion connector.
 

Twospruces

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I wasn't thinking to replace this drive with a CF card, but rather to add a CF card. But, fair enough I could just replace the 20MB drive with something else.
The PC-6220 uses a 20MB Connor drive, which has 50 pin interface.

The below page is from the service manual, which describes the 50 pin interface for the Connor 20MB drive.

connor2.JPG

There is a special flex cable that connects the drive to the main PCB. It connects into two sockets on the motherboard.
Those pinouts are here.


connor2.JPG


Well the drive works fine now, and tests clean.
Still, I would like to figure out how to make use of an XT-CF adapter in this, as it would give me a nice fast drive and a convenient way to transfer files.
 
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