Intertec Super Brain question

[Allison]

>
>Subject: Re: Intertec Super Brain question
>   From: Fred Cisin <cisin at xenosoft.com>
>   Date: Fri, 07 Jul 2006 19:14:51 -0700 (PDT)
>     To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On Fri, 7 Jul 2006, Chuck Guzis wrote:
>> I've got a load of Super Brain CP/M diskettes and find that for whatever
>> reason, the DAM (data address marks) seem to vary wildly on a disk-to-disk
>> sample.
>> What did the SB use for a diskette controller and why the varying DAM's
>> (sometimes it's just a single sector or group of sectors on a track)?
>
>I've been told (but can't personally verify), that it's 179x

1791 (they use inverted data and everything If memory serves).
Same as the 1793 only the data bus is inverted.  They use the 
inversion to make their files less readable.  They were, 
till everyone figured it out.

>They sure screwed up that format, didn't they?
>
>The data is inverted relative to the address marks,
>the index address mark is often too early for an NEC
>(I often have to disable the index pulse to read them),
>the head numbers on the second side are often wrong,
>and I have no idea why the data address marks are flaky.
>And they called DSDD 48tpi "quad" density, which meant
>that when they came out with DSDD 96tpi, they called
>that "Super Density", and abbreviated it "SD"!
>(what is the next larger size of olives?)

Classic case of the 179x could so they did.  Didn't make it a good 
idea or even comforms to any standard.

>
>The good news is that it usually doesn't object to a properly
>formatted diskette, so it's often possible to format a stack
>of diskettes; use the SB to copy the files to them, and then
>bring those diskettes back to read.
>
>
>I tried to talk to Intertec about their formats.
>At NCC '83, some of their suits told me that they could
>not imagine ANY possible reason to convert data between
>disk formats, other than to steal their "proprietary"
>software (CP/M?), and that they would file a lawsuit if
>I included any SB formats in XenoCopy!
>That night was the first time that I ever added formats
>to XenoCopy in a hotel room.
>They never kept that promise.

Yes there was the liklyhood that it meant more useful software 
would be available for the 'brain.  Likely took them longer than 
a slow 8008 for that being a good thing to occur.

>They used to have a sizable hobbyist following!

Never seen that many though they were nice to use.


Allison

>
>--
>Grumpy Ol' Fred     		cisin at xenosoft.com
>