Looking for an 8 bit FDC...

[Christian Corti]

(All always, the list management is broken, I don't have Allison's posting 
yet, but the answers this posting...)

On Tue, 25 Oct 2005, Fred Cisin wrote:
> The IAM interval is easily handled by masking that signal.  (interrupt the
> cable, or (on older cruder drives) cover the index with tape.)

As a note: The IAM is not defined by the IBM standard, there's no IAM on 
3740 (FM) or System/34 (MFM) diskettes.

> On Tue, 25 Oct 2005, Allison wrote:
>> Who does 128byte MF sectors???  If you really have to it's
>> possible to tell a 765 that it's a short sector in mfm.

Robotron for examples uses 128 bytes/sect. MFM so they have 26 sectors per 
track on a 96 tpi DD 5.25" diskette and have the standard 8" FM sector and 
track layout.

> I have half a dozen formats that I was unable to put into XenoCopy,
> due to 128 MFM.  I never could get reliable reading, so I did those with
> a 1791.

I have several PCs and Multi I/O ISA controller cards that can do 128 
bytes/sect. MFM. Watch out for the NatSemi DP8473 FDC.

Christian