At first, on my retro Z80 (RC2014) computer, I was using the assembler that came with CP/M, named ASM. Later on, looking for the Z80 block transfer instructions and not able to find them, I found out that it is an 8080 assembler. (hey, it’s been a long time since I programmed the Z80)…
A net search led me to Matthew Reed’s development tools.
He developed an assembler named Z80Asm. It is worth checking it out! The free version has a few restrictions (see the bottom of It’s page). The paid version can produce Z80 *.com files, that can be run on the RC2014 Z80 CP/M computer.
The second program he developed is a disassembler, Z80Disasm.
After contacting him, he graciously granted me permission to share the PDF files I made with the contents of these pages. You can visit my GitHub page to find them, especially this folder.