@fuzzweed.co.uk That works for me. Assemble on a modern assembler using ORG $100 (with RST 0 rather than RET at the end). Name the raw binary (no headers) SOMETHING.COM and copy it to the A: drive.
I’ve got CP/M 2.2 on the RC2014 and tried it on CP/M Plus on the Speccy as well.