ISA ( PC ) 8" floppy disk CONTROLLER ???

Chuck Guzis cclist at sydex.com
Wed Feb 4 16:50:48 CST 2015


According to my documentation, there are two programmable signals 
brought out on the 34-pin headers as well as the 37 pin D-sub.

Pin 2 on the 34-pin is connected to pin 3 (note D-sub numbering 
conventions as contrasted with 0.10" header conventions) on the DC37 
connector.  Pin 6 on the 34-pin header is connected to pin 5 on the DC37.

2 is specified as "Mode 1", which is normally used as a density-select 
on 5.25" drives, but is used as a RWC signal on 8" drives.  Pin 6 is 
specified as "Mode 2", which is NC on the 8-inch cabling.  Normally, pin 
6 is used to control 2.88M or 3-mode drives.

--Chuck


On 02/04/2015 01:45 PM, Mike Stein wrote:
> Is TG43 available on both the internal 34-pin and the external DC(DB)-37
> connector on the CompatiCard? Some old posts suggest that it's only
> output externally, but the CC manual seems to treat both internal and
> external connections to an 8" drive equally valid.
>
> m
>
>
> ----- Original Message ----- From: "Chuck Guzis" <cclist at sydex.com>
> To: <General at classiccmp.org>; "Discussion at classiccmp.org:On-Topic and
> Off-Topic Posts" <cctalk at classiccmp.org>
> Sent: Wednesday, February 04, 2015 3:32 PM
> Subject: Re: ISA ( PC ) 8" floppy disk CONTROLLER ???
>
>
>> TG43 is also sometimes called "RWC" for reduced write current.  On
>> many later 8" drives, this is a NC.
>>
>> --Chuck
>>
>>
>>
>>
>> On 02/04/2015 10:58 AM, Ali wrote:
>>>>> So are you saying that with a CC IV you don't need the DBIT adapter,
>>>>> for writing, and just need the 34pin to 50pin converter?
>>>>
>>>> Yup.   The wiring of the 34-to-50 position connector is also documented
>>>> in the CC manual.
>>>>
>>>
>>> Chuck,
>>>
>>> I've seen the wiring info in the manual and I just looked through the
>>> PDF
>>> version of the manual I have. I could not find any mention of TG43 in my
>>> quick look through. Do you by any chance know where the info is? Thanks.
>>>
>>> -Ali
>>>
>>>
>>>
>>
>
>
>



More information about the cctech mailing list