**NEW** TRS-80 Model 4/4P I/O Interfacing
A summary of I/O Ports and bit definitions for Serial and Printer Ports.
Click here for Model 4/4P I/O Interfacing
19200-baud Serial Boot Loader for TRS-80 Models 3/4/4P
for PC host:
v1.0 -- Serial Boot Loader for TRS-80 Model 4P
Copyright (C) 1999, Douglas Beattie Jr.
for PC host:
v1.1 -- 19200-baud Serial Boot Loader
(with Terminal Mode) for TRS-80 Models 1/3/4/4P
Copyright (C) 2000, Douglas Beattie Jr.
for TRS-80 targets:
**NEW** SBOOT4/CMD and SBOOT3/CMD
Originally for the Model 4P only, the above DOS utilities can be used
in conjunction with the /CMD Serial Boot programs, SBOOTX.ZIP
(8K) which run on any TRS-80 Model 3 or Model 4 disk system (and I
assume a Model 1 also, but I haven't verified this.) You can use
Keil's emulator to put the appropriate standalone serial boot /CMD
program onto a TRS-80 floppy disk.
Here are some Notes
about Model 4P Serial Boot
Attention Z80 Programmers!
You can cross-develop TRS-80 applications (or standalone Z80 apps too)
from your PC, using the utilities above. To save them as a /CMD file, cross
assemble without an argument to the END statement, upload the program,
reboot the TRS-80, and use the DUMP command from TRSDOS to create an executable.
(This is how I created the /CMD version of MEMSPY (see below).
Z80 FORTH System with source code
See the TRS-80
My own Z80 Programs with Z80 Source Code
ALSO: here's a nifty program to upload into your TRS-80 Model 3/4/4P:
(5K) uses Mode 1 interrupts and demonstrates animated low-resolution
graphics. Z80 Source code is included. Assembler used is the Zilog
Macro Cross Assembler (640K DOS Version).
(6K) is a modular version of the above. This package of Z80 source
code will demonstrate the use of modules and linking with the
And a package for TRSDOS/LS-DOS, same as above, assembles with EDAS:
NEW: MOD3G, modified to build using
(Zilog Developer Studio) under Windows. Also includes 4_MHz speedup,
and different pattern speed: MOD3GZDS.zip
MEMSPY -- Memory Spy
Here's a utility to examine memory, as after a program crash, or unusual
system behavior such as lock-up. For the
Models 3, 4, and 4P, it can also look into banked memory on a 128K
system. Z80 source code is included Download MEMSPY.ZIP
(19K) and check it out.