15 Jun
2021
15 Jun
'21
8:47 a.m.
On 6/15/21 8:58 AM, Tony Duell via cctalk wrote:
On Tue, Jun 15, 2021 at 6:34 AM Tom Uban via cctalk
<cctalk at classiccmp.org> wrote:
I did not mean to imply that you had changed the behavior in your KM11
design.
You are surely a competent and trusted pdp11 resource :)
--tom
My KM11s are based on Tony Duell's schematic
and if you look, switches S3
and S4 are both driving outputs rather than simply switching them to ground,
so I don't think two boards at one time would work if these signals are simply
tied in parallel on slots A2 and B2.
I took the switch circuits from the offical
KM11 schematics which are
either in the PDP11/45 CPU printset or the RK11-C printset that I
have, I forget which. I certainly didn't add logic or replace
open-collector parts with totem-pole ones.
-tony