FujiNetWIFI/fujinet-firmware

Improve CP/M printer performance.

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#918 opened on Apr 24, 2025

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enhancementhelp wanted

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Description

CP/M printer performance is slow.

This is because we are sending each individual character to the virtual printer, one character at a time conforming to the CP/M BIOS function.

see: https://github.com/FujiNetWIFI/fujinet-firmware/blob/master/lib/runcpm/cpm.h#L637 and: https://github.com/FujiNetWIFI/fujinet-firmware/blob/master/lib/device/sio/printer.cpp#L115

The buffer in question happens to be 320 bytes long, so up to 320 bytes can be sent to the printer in print_from_cpm(), which would vastly speed up the process, and using a timer to indicate when to flush the buffer (assuming less than 320 bytes is in it)

-Thom

Contributor guide

Research direction
Investigate the CP/M BIOS print function and the SIO printer driver to implement buffered output with a flush timer.
Tech stack
c
Domain
backend
Issue type
Performance
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
CCP/M BIOS
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
45