flash (or ide) storage for unibus 11?

Mike Ross tmfdmike at gmail.com
Mon Nov 23 18:23:21 CST 2015

On Tue, Nov 24, 2015 at 1:11 PM, Rich Alderson
<RichA at livingcomputermuseum.org> wrote:
> From: David Bridgham
> Sent: Monday, November 23, 2015 11:30 AM
>>> For a classic/straightforward programming interface, the Massbus disks (RP04
>>> and successors) are a good choice.  That will take you just over 500 MB, if
>>> you emulate the layout of the RP07.
>> Current thinking (at least my current thinking) is RK11 first then probably
>> RP11, both optionally extended to support Q22 addresses.
> Why bother with the RP11?  The RP03 gives you a maximum of 40MB (20MW) per disk.

Because, blinkenlights! :-)

There was an RP11, an RP15, and an... RP10? Lots of blinkelights,
covers 3 of the 4 main architectures.

There IS something neat about retaining enough of the physical side of
things to be recognizable in emulation... having a controller box with
blinkenlights, and ports into which you plug your RP03s... even if the
RP03s are memory sticks and the physical interface is USB...

>> Finally, most likely the RH11 for some Massbus disks with 22-bit addressing.
> Be careful with the RH11 (and other Massbus interfaces):  DEC lied in their
> published descriptions of the signals.  In particular, 2 important ones are
> interchanged in the tables.

I seem to remember Massbus wars, and DEC having a strategy to use IP
to lock out plug-compatible competition... was unpublished or
inaccurate information part of that, I wonder?


'No greater love hath a man than he lay down his life for his brother.
Not for millions, not for glory, not for fame.
For one person, in the dark, where no one will ever know or see.'

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