chumicro-repl¶

Host-side serial REPL for CircuitPython and MicroPython boards.

Interactive TUI with traceback highlighting + a programmatic ReplSession for headless test fixtures. Runs on your laptop — not on the board.

Quick example¶

from chumicro_repl import ReplSession

with ReplSession("/dev/cu.usbmodem14101") as session:
    session.exec("import os")
    sysname = session.call("os.uname")
    print(sysname)

Or use the CLI — point it at a serial port path:

chumicro-repl --address /dev/cu.usbmodem14101

Press Ctrl-X to quit; Ctrl-C / Ctrl-D / Ctrl-E are forwarded to the board, matching the mpremote repl keybindings. On connect, chumicro-repl prints a dim banner with the connection details and key hints, and nudges the friendly REPL to reprint its >>> so you don't sit at a blank screen.

What you get¶

• Interactive TUI — a thin, mpremote-compatible terminal that streams the board's REPL with traceback highlighting, a startup banner that names the connection + keybindings, and auto-reconnect when the cable drops mid-session.
• InteractiveReplSession — sibling of chumicro_deploy.RecoveringDeployer. Wraps ReplSession with classification + retry + coaching for session-start failures.
• tail(device, seconds) — stream the friendly REPL for a window, fail fast on a traceback, return an ExitCode. Useful as a post-deploy follow-up step.
• ReplSession — programmatic raw-REPL context manager. exec(code), call(function_name, *args, **kwargs), read_until(pattern, timeout) for headless test fixtures.
• detect_patterns / colorize — streaming pattern detector + ANSI renderer for CircuitPython Traceback, safe mode, Hard fault, MicroPython Traceback, and MicroPython MPY: soft reboot banners.
• chumicro-repl CLI — --address, --baudrate, --tail, --no-fail-on-traceback, --mode {line,passthrough}.

Documentation¶

• User Guide — getting started, each surface explained, runtime notes.
• API Reference — full API from the source docstrings.

Install¶

pip install chumicro-repl

No bundle registration needed — chumicro-repl is a host tool, not on-device code.