(last update on 28 Oct 2023)
RTM/Z80 is a multitasking kernel, built for Z80 based computers, written in Z80 assembly language, providing its users with an Application Programming Interface (API) accessible from programs written in the C language and the Z80 assembly language.
It is intended to be a simple and easy to use learning tool, for those who want to understand the tips and tricks of the multitasking software systems.
Current version is 2.6
RTM/Z80 can be used on the following environments:
• Z80SIM Z80 simulator (e.g. on Windows, under CygWin)
• Z80ALL standalone homebrew Z80 computer (25MHz Z80, 4 x 32KB RAM, KIO, VGA, PS/2, DS1302)
• RC2014 homebrew Z80 computer, using the following hardware configuration options:
o SC108(Z80 + 2x64KB RAM) + SC110(CTC+SIO) , or
o SC114(Z80 + 2x64KB RAM) + SC110(CTC+SIO), or
o any Z80 board + 64/128KB RAM + SC110(CTC+SIO) , or
o any Z80 board + 512KB RAM+512KB ROM Memory Module + SC110(CTC+SIO)
• RCBUS based homebrew Z80 computer, using the following hardware configuration options:
o SC706(Z80) + (SC707 / SC714 RAM) + ( SC716(SIO) + SC718(CTC) ) / SC725(CTC+SIO)
• any CPU Z80 board supporting IM2 + any 64KB RAM board + any CTC board + any SIO ( or KIO board ) (in this case, the I/O ports must be set in the source code, see manual, chapter Porting RTM/Z80 to other hardware)
The mandatory hardware requirements: 64KB RAM, support of Z80 Interrupt Mode 2, CTC, SIO or KIO.
New in v2.4 : improved communications I/O support
see DEMO folder for getxfile, putxfile (XMODEM compatible)
New in v2.5 : KIO support added
New in v2.6 : Z80ALL version added,
VGA display support added for Z80ALL,
VGA System status display added for Z80ALL,
PS/2 keyboard support added for Z80ALL,
extra 2x32KB RAM support added for Z80ALL,
real time clock DS1302 support added for Z80ALL
(see source files in the DEMO folder)
RTMDEMO.MP4 - 2 concurrent games, executed on RC2014
BIRDS.MP4 - the 'birds, eagle & kite' game, executed on Z80ALL
( only for Z80ALL version )
(running)
(after shutdown)
For Z80ALL, the "RTM/Z80 system status", displayed in real time during the execution of a multitasking application, is very useful for:
- assessing the dynamic memory load ( is it dangerously close to the maximum capacity? )
- viewing the task execution dynamics ( the tasks active <---> waiting switching )
- learning about the system load ( how long, in %, stays the system idle - is the % dangerously low ? )
- learning about the tasks stack size ( is the remaining space in stack dangerously low ? )
Using the real-time VGA system status display, a multitasking application can be fine-tuned, in an efficient way.