ddc@druxp.UUCP (CusterDD) (02/22/84)
==== < < ... on the lowly PDP-8 (with NO index registers) ... < I'm astonished! What about the 16 (8 auto incr., 8 auto decr.) "index registers" in page0? :-) DEC referred to them as "index registers," (hee! hee!! HAW!!). And the Time-share 8? I guess CDF and CIF had their benefits, but ... Talk about inconvenient!! David Custer druky!ddc
stevek@umcp-cs.UUCP (02/23/84)
The PDP-8 has 8 page zero auto-inc registers but DG expanded? this feature? on the NOVA to 8 page zero auto-inc AND 8 page zero auto-dec registers. Sigh! if they (DG) had only made it possible to use them so that they mappped to the same locations ... then we could use them as stack pointers - an indirect thru 20-27 would auto-inc and 30-37 would auto-dec . Voila stack pointers. This message brought to you via a NOVA 830, 192kbytes ,RDOS system. Stephen Kogge University of Maryland Department of Computer Science
jonab@sdcrdcf.UUCP (Jonathan Biggar) (02/23/84)
In article <560@druxp.UUCP> ddc@druxp.UUCP (CusterDD) writes: >==== >< >< ... on the lowly PDP-8 (with NO index registers) ... >< > >I'm astonished! What about the 16 (8 auto incr., 8 auto decr.) >"index registers" in page0? :-) > >DEC referred to them as "index registers," (hee! hee!! HAW!!). There are only 8 auto-increment "registers" on a PDP-8, (locations 10-17 in page 0), and no auto-decrement "registers". I should know, I used one for 6 years. Jon Biggar {allegra,burdvax,cbosgd,hplabs,ihnp4,sdccsu3,trw-unix}!sdcrdcf!jonab
ron%brl-vgr@sri-unix.UUCP (02/25/84)
From: Ron Natalie <ron@brl-vgr> I'll never again use a machine with only 8 instructions.
matt%ucla-locus@sri-unix.UUCP (02/25/84)
From: Matthew J. Weinstein <matt@ucla-locus> In fact, althought PDP-8's do not, Nova 800's do have 8 auto-increment and 8 auto-decrement registers (020-027 and 030-037 resp.)