unibus geeking; udisk update

[Brad Parker]

[keywords: unibus, pdp-11, disk controller emulation]

If anyone has an interest in low level unibus, I scanned in some screen
shots from my simple HP1650 and updated my udisk page.  Nothing exotic,
just basic register reads, npr & br5.

      http://www.heeltoe.com/retro/udisk/index.html

I finally put the async cpld aside and started debugging the simple
synchronous state machine.  The sync version works much better and is
(as you'd expect) much faster.  I have some more debugging to do but
basic register i/o and dma work well and the cpu can now easily keep up.

I hope to prove out the prototype this summer and do a spin modulo
work load.

(last week all 3 of my 'real jobs' stalled simultaneously - woo hoo!
this week i have a pcb board stuck in customs in boston, so my fun
work is getting a time slot or two :-)

-brad