Posts in Z80
Comparing writing “Hello World” using DDT versus ASM in CP/M
- 29 September 2024
Using DDT
, one can use the inline assembler to write small programs.
Besides DDT
, CP/M also offers ASM
to assemble a bit more
advanced programs. In this blogpost, I will use both programs to write a small
“Hello World” program and compare the workflow between the two procedures.

Driving serial communication in CP/M on the P2000C using Z80 assembly
- 22 September 2024
The Philips P2000C, despite allowing for a 8088-CoPower Board, was in the first place a CP/M machine. CP/M (Control Program for Microcomputers) was an early operating system developed by Gary Kildall in 1974 for Intel 8080 microcomputers. It became one of the first widely used OS for personal computers, providing essential features like file management, device input/output control, and program execution. CP/M was particularly influential because it allowed software to run on different hardware platforms, establishing an early form of software portability. It laid the groundwork for future operating systems and influenced the development of MS-DOS, which became dominant in the 1980s. CP/M’s impact is significant in the history of personal computing.
