[HECnet] RSTS/E is really picky

[Johnny Billquist]

On 2014-05-20 21:39, Dave McGuire wrote:
On 05/20/2014 11:04 AM, Johnny Billquist wrote:
M+ do not need split I/D-space. But you do need 512K of memory. But
the 11/23 and 11/24 are supported CPUs.

I have 1M of memory.

Sure you're not confusing the 11/23 with the 11/23+?   I was poking at
4.6M+'s SYSGEN and it wouldn't accept 11/23 as an answer.

The difference between the 11/23 and 11/23+ is the amount of memory. The
original 11/23 could not go above 256K... If you have more, then you
actually have an 11/23+.

    In practice, though, the vast majority of systems out there that say
"PDP-11/23" (not -PLUS) on the front are in fact capable of 22-bit
addressing; you've gotta look at the etch rev of the CPU board.   See my
other email.

Aha. Thanks for the information, Dave. I knew that very few 11/23 systems really were limited to 18 bits, but I didn't know exactly which ones. So even the M8186 boards are mostly 22-bit. Really nice to know.

	Johnny