Qbus to CF / IDE

[Allison]

>
>>Subject: Re: Qbus to CF / IDE
>>   From: Doc Shipley <doc at mdrconsult.com>
>>   Date: Fri, 29 Feb 2008 19:09:12 -0600
>>     To: General Discussion: On-Topic and Off-Topic Posts <cctalk at classiccmp.org>
>>
>>tiggerlasv at aim.com wrote:
>>> 
>>> 
>>>>  You could have, for example, four RL02s each capable of being
>>>>  assigned a "pack" from the card.
>>> 
>>>>  What were the biggest non-MSCP-attached drives?
>>>>  How hard would they be to emulate?
>>> 
>>> 
>>> While RL02's would probably be easy to emulate,
>>> at 10MB a pop, you don't get alot of bang for your buck.
>>
>>   Forgive me if this is a silly question, but is 10MB a limitation of 
>>the firmware and drivers, or of the disk technology?
>
>None of the above.  There is a limit of 32mb for RT11 disks because 
>because the sector pointer is only 16bits and sector size is 512bytes
>(65536*512=32mb).
>
>The real problem is few people know how to write a driver and if they 
>do it's only for one OS and the list of OSs [UnixVn, RT11, RSTS, 
>RSX11, VMS, Ultrix, other?] means a driver for each.  Once you have 
>a working driver a booter is possible.
>
>The RL driver cant be used as it's dependent on DMA and a simple IDE
>interface will not likely include that.  So the model for the driver 
>is more likely DD[tu58], DX [rx01], DY[rx02] or maybe some other but
>with the dimension table altered as they used PIO for the transfer.
>
>
>Allison
>
>
>>
>>	Doc
>
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