[HECnet] DU11 vs. DUV11

[Johnny Billquist]

On 2013-01-06 21:47, John Wilson wrote:
I still can't find where it says "8085A" in the 110/130 manual, but page
B-3 gives I/O page timings and mentions an "I/O microprocessor" and the
fact that word I/O takes 90 usec but byte I/O takes 180 usec.   So that
certainly explains the difference in the DUV driver.   Plus the manual
specifically says that RSX11S is available for the /110, so I guess it
was even supported!   Sweet.

Also mentioned on page 4-6, but pretty much with the same level of detail. Byte writes cause a read-modify-write. Time of 180 usec. And there is an (unmentioned) 8-bit microprocessor acting in between the PDP-11 and any peripherials.

	Johnny

-- 
Johnny Billquist                                   || "I'm on a bus
                                                                  ||   on a psychedelic trip
email: bqt at softjar.se                         ||   Reading murder books
pdp is alive!                                         ||   tryin' to stay hip" - B. Idol