On Mon, 13 May 2013 17:48:03 -0000, you wrote: Patching the monitor should be doable without many problems, and I did that to use the idle feature of KLH10 before being able to build a new custom monitor. The harder part could be to find the symbol name for the word containing the DECnet address, then everything should be quite easy. I'll try to find that symbol name... :) Thank you. Well, here are the symbols: M.SNAM is the system name (apparently not related to DECnet) M.DNAM is the DECnet node name M.LNAM is te LAT (default?) service name M.DHOM is the DECnet area number (octal!) M.DNUM is the DECnet node number (octal!) Beware: the names are SIXBIT strings, so you must discover how to input SIXBIT vaules with FILDDT (I have no idea, probably it's something like <ESC>letter). This is the most updated DDT (and FILDDT) manual: http://pdp-10.trailing-edge.com/tops10v704_docc/01/10,7/docupd/ddt.mem.html Then there is a good book about TOPS-20 Macro programming, which is useful even in a TOPS-10 environment, and which does explain quite well how to use DDT and FILDDT. The book is by E. Gorin and here you'll find directions to download it in PDF from a TOPS-20 site: http://www.bourguet.org/v2/pdp10/ (If it does not work I'll put a copy somewhere for you to grab.) The reason I'm not using 7.04 is due to the missing 7.04 DECnet tape. Has someone found a working one I'm not aware of? I used the following tape images from Trailing Edge: This one to boot (it works but the monitor into this tape doesn't keep time, so you may well use TWONKY to create a boot tape with a working Monitor, way better than the one into the KLAD pack): BB-FI81B-DD Identified as "KLAD10-7.04-A TAPE 1/3 1989" These for system programs and utilities (i.e. most of TOPS-10): BB-X128C-SB CUSP (Commonly Used System Programs) 1 of 2 BB-FP63B-SB CUSP (Commonly Used System Programs) 2 of 2 BB-X130C-SB Customer Supported Tools BB-FP64B-SB Unsupported Tools This one for DECnet (7.04 version, the latest available): BB-X116D-BB Identified as "DECNET-10 V4.0 SUP 16MT9 1989" These for compilers, etc.: BB-D480G-SB Fortran V11 (the only one available, incomplete but usable) BB-H580E-SB Cobol V12C and Sort V4D, identified as "BB-H580E-SB_1985" BB-D478D-BB Identified as "DBMS V5A" This one to rebuild a good monitor from sources: BB-X140C-SB Monitor 7.04 sources Additional keys to decrypt patches (other keys are bundled with products): BB-PANKA-BB Identified as "TOPS-10 SORT V4D" Patches to update TOPS-10 to 7.05 (!): BB-BT99V-BB "TOPS-10 704 TSU04 TP 1 OF 3 1990" BB-JR93N-BB "TOPS-10 704 TSU04 TP 2 OF 3 1990" BB-PBDED-BB "TOPS-10 704 TSU04 TP 3 OF 3 1990" Moreover, the tape identifed as "TOPS-10 and TOPS-20 Integration Tools V9, 3-Aug-1986" contains some tidbits such as a TOPS-10 version of the EDT editor which can be quite useful when working with sources. All of the above could be found on Bitsavers too: http://bitsavers.informatik.uni-stuttgart.de/bits/DEC/pdp10/magtape/dec_dis… There are problems patching Fortran because there are no keys available to decrypt patch files. Or that was the evidence when I made my last TOPS-10 installation. But now I've found some notes about some Fortran-20 key files that might work with TOPS-10 Fortran too, but I never tried (IIRC)... HTH, :) G.