DEC pdp 11 "R-K ABBR. BOOT P. C. Board"
jnc at mercury.lcs.mit.edu
Thu Oct 8 08:30:37 CDT 2015
> From: Jay Jaeger
> one ought to first check whether the board is intended for a UNIBUS or
> Q-Bus system!
Easiest way to do that is to look on the back side at the fingers; if the
board does not do interrupts or DMA (likely, if this is a ROM card), there
will be U-shaped traces to 'jumper' the grant lintes: a QBUS card will have a
pair, with a single finger space between them; a UNIBUS card will have a
group of four, with no spaces between them. Either pattern is absolutely
definitive. If you don't see either... time to drag out the ohm-meter! :-)
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