1 Jan
2019
1 Jan
'19
6:43 p.m.
From: Paul Koning
> I haven't sat down with -C and -D manuals and
done a bit-by-bit
> compare. I just did that (I used the "RK11-C Moving Head Disk Drive
> Controller Manual", DEC-11-HRKA-D, and the 1976 "Peripherals
Handbook"),
> and found in the following:
> In the RKDS: bit 7 has changed the definition slightly ("Drive Ready"
> to "R/W/S Ready"), but seems to be basically the same.
You mean bit 6? Bit 7 is "drive ready" in
both.
@*#$@*$%@&*!!!!! My silverfishionado nature screwed me! I didn't have an
RK11-D manual in paper, so I relied on the "Peripherals Handbook" - and
it's
got an error!
In both the 1975 and 1976 edition, the _diagram_ for the RKDS shows bit 7 as
"R/W/S Ready", and bit 6 as "Access ready", but the _table_ shows bit
7 as
"Drive Ready", and bit 6 as "R/W/S Ready"! OK, so let me ditch that,
since
it's self-contradictory, and thefore necessarily erroneous.
I'll switch to the RK11-D User's Manual, EK-RK11D-OP-001. It gives bit 7 as
"Drive Ready", and bit 6 as "R/W/S Ready". (The RK11-C manual gave bit
7 as
"Drive Ready", and bit 6 as "Access Ready".)
Bit 6 has a different name in the two descriptions but
the meaning
appears to be the same.
Yup.
Thanks for catching that for me!
Noel