PDP-12 at the RICM

Rich Alderson RichA at LivingComputerMuseum.org
Mon Jul 13 17:54:20 CDT 2015

From: Noel Chiappa
Sent: Monday, July 13, 2015 1:10 PM

>> From: Rich Alderson

>> PDP-12	12-bit word, PDP-8/i + LINC hybrid

> Err, DEC sold a PDP-8/LINC hybrid themselves (interesting machine, it's
> covered in one of the standard PDP-8 processor manuals), before the PDP-12
> came out; the -12 was basically a re-engineered version of the 8/LINC.

As noted by Christian Gauger-Gosgrove, I was only listing "PDP-n" systems.

The LINC-8 was not really a hybrid so much as a triumph of packaging.  It
contained a complete PDP-8 ("Straight 8") CPU and a complete LINC CPU, the two
capable of accessing the same 12-bit memory.  Changing from PDP-8 operation to
LINC operation was a matter of a physical switch.

The PDP-12 is different.  It is essentially an enhanced PDP-8/i which can also
execute the LINC instruction set; each instruction set has an instruction to
change to the other mode of operation, so that a single program can contain
routines written in both.  That is why I called it a hybrid.


Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134

mailto:RichA at LivingComputerMuseum.org


More information about the cctech mailing list