WD33C93A-PL 00-08 is extinct. What now?

idr

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For all practical purposes, there are no more WD33C93A-PL 00-08 chips. These are sought for the Amiga 3000 and others. While the DIP package seems to be gone, the PLCC version seems to have some availability... as long as you don't mind ordering parts from China or Hong Kong. The PLCC version is 44 pins (versus 40 for the DIP). There are three added "no connect" pins, and a DP pin that "is used only for checking and generating parity during data transfers." If the driver does not enable host-data parity checking, I believe this pin could be allowed to float. Building an adapter should be trivial.

I've spent a few hours searching the net for information about the various chips in the WD33C93 family. I have been specifically looking for version related errata. I've looked in the original data sheets for both the WD33C93A and WD33C93B, and I've looked in the Linux driver source. I've come up empty handed.

Here are my questions:

1. Aside from different packaging, is a WD33C93A-JM 00-08 the same as a WD33C93A-PL 00-08?

2. The WD33C93B data sheet says the WD33C93B "may replace the 33C93A with no modification to the hardware or the firmware." There appear to be several revisions of the WD33C93B. Which, if any, have the fixes from the WD33C93A-PL 00-08? I have seen at least 00-06. The nice thing about the WD33C93B is that a modified scsi.device ought to be able to enable Fast SCSI transfers.

3. How do the AMD parts compare? Am33C93A-16PC chips are quite available. I've noticed that some GVP boards used the AMD chip, and I don't recall those having the problems of the pre-00-08 WD chips. AMD doesn't seem to have made a B replacement.
 

idr

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as far as I know, the AMD chip is a drop-in replacement...

Yeah, I inferred that from comparing the data sheets. I was more wondering about known bugs... as the pre-00-08 WD have some issues on at least the Amiga 3000 multiple drives, etc.
 

hooverphonique

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I would just get an AMD part and not risk getting a counterfeit "original" from china..

PLCC->DIP adapters are available abundantly for a few quid.. The reason for 44 pins on the PLCC is that there is no such thing as a 40 pin PLCC, and the nearest larger size is 44.
 
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