To install this package on CP/M, download the ZIP file and unpack it. It will create a folder with the same name as the package, containing the files shown.

Download PSA-TDL-PASM-PLINK.zip containing all files below.

README.TXT
----------

Phoenix Software Associates (PSA) and Technical Design Labs (TDL)
Macroassembler and Overlay-capable linker
Special TDL HEX loader

15 april 2026

These programs are very sophisticated tools for the z80/8080. It took some
effort to gather these programs and files together in one place. The files in
this bundle were gathered from multiple sources found on the net (and stored in
directories on my own disk drive). If you have more, or find problems, please
email me at tom at bleeve.me

Neil Colvin at TDL/Xitan wrote ZASM and ZLINK, a full featured Z80 macro
assembler and overlay-capable linkage editor (unrelated to Cromemco's programs
of similar names). After TDL/Xitan's demise PSA was formed by Neil Colvin from
the ashes of TDL/Xitan and apparently Neil retained rights to these programs,
and renamed them PASM and PLINK (then later PLINK-II). 

PASM and PLINK are newer than ZASM/ZLINK, and may contain fixes and features
not in the TDL programs. I have not puzzled that out yet. PASM does assemble
TDL assembly, and gives slightly improved error messaging. Manuals are
available for both in the Docs section.

They use TDLs instruction mnemonics, which are "extended intel", and not the
Zilog implied-orthogonal instructions.  The overlay source files refer to PSA
by name but I found them on the net associated with the TDL linker.

PASM/ZASM output linkable object or .HEX files. The .HEX files can include
extended features (symbols, separate .DATA and .CODE segments, and more) if
those directives are in the source. For these .HEX files you will need to use
TDLOAD or HEXCOM to convert to absolute, executable binary.

FILES IN THIS BUNDLE

PSA and TDL versions of assembler and linker. Subtleties of the different
versions not yet explored; they seem functionally interchangable, 45 years
later.

PASM.COM
PLINK.COM
ZASM.COM
ZLINK.COM

These are copies of the same but taken from johnsonjh's VEDIT github repository
(itself very interesting!). I added the leading "V" to the name so that they
can remain identifyable and functional when copied to CP/M.  I have not done so
much as a diff; but they run under CP/M and MP/M. 

Vpasm.com
Vzasm.com

These are also from johnsonjh's VEDIT repo, with the leading "V" added as per
above. HEXCOM also converts TDL .HEX format to .COM; it may be "TDLOAD" in
another guise. I don't know what POPCOM is.

Vpopcom.com
Vhexcom.com

This is TDLOAD, the TDL extended HEX format to .COM converter. It assembles
with Digital Research ASM.

README.TDL
README.TXT
tdload.asm
tdload.diff
tdload.orig

These are PSA overlay loader modules. (I used the x86 versions of
these in Fido/FidoNet with Lattice C then Microsoft C.)

exec101.asm
execute.asm
overlay8.asm
overlay.asm
overlayd.asm
overlayz.asm
ovl105.asm
ovl203.asm
ovlbld.sub

-30-

--------------------