BLKLDR 1 is from the IMLAC; IML DEVICE archive file dated 1976-11-02.
The archive was found in three identical copies on ToTS tapes 7006990,
701351, and 90606; they were extracted by Brad Parker. The BLKLDR 1
timestamp inside the archive is 1975-01-26. Tape database records
from DM show a BLKLDR 4 dated 1974-08-19.
To build the IMLAC; IMLAC BLKLDR file, it's first assembled with
MIDAS. Regular IMTRAN writes the block loader format, but the block
loader itself is in the "special TTY" boostrap format. IMTRAN is
runtime patched to skip the block framing.
The file IMLAC; SSV 52 dated 1973-01-07 was edited to match the Imlac
block loader format file http://www.ubanproductions.com/Imlac/ssv,
which claims to be SSV 22. SSVMSE 38 from 1977-12-13 was also helpful
in the process.
IMSRC; SSVCHR 22 is entirely from disassembly. The original file
would have been machine generated by SYMFOR.
The LOADER subroutine breaks MAZE because it pushes all code higher,
making constants and WALLS cross over 14000. It's also unnecessary
since setting the start address to 101 jumps back to SSV which will
accept the next data block sent from the PDP-10.
A possible explanation is that LOADER was added by someone running
MAZE without SSV. No other version of the MAZE source code has
LOADER.
This is assembled with MIDAS, and then translated with IMTRAN to an
ASCII form suitable for uploading to an Imlac terminal. MOUSE is
enabled to ensure the MSW opcode is defined.
