regtable (Python)

Host-side tools for regtable, the C99 register-table library for MCUs: one RegEntry[] table in the firmware, reachable over a serial CLI, Modbus RTU/TCP, MQTT, a browser, and Python.

pip install regtable

Command line

regtable gen device.yaml -o gen            # registers.c/.h/.md + <device>_client.py
regtable connect -p COM6                   # the board's own table, then a REPL with `dev`
regtable watch a0 led -p COM6              # print changes; --json for scripts
regtable connect -p COM6 --yaml device.yaml  # typed client, verified against the board first
regtable serve                             # the Web Serial panel on localhost

Without --yaml, connect and watch take the device as it describes itself (list --json) and reach registers by name: dev["led"], dev["pwm9"] = 128. With --yaml they build the typed client from the YAML in memory and compare the board's table field by field with it; a board whose table differs ends the command with the differences listed, before the first read.

Typed client

from regtable import build_client

UnoDevice = build_client("uno.yaml")       # or import the generated <device>_client.py
with UnoDevice.serial("COM6") as dev:
    dev.led = True
    dev.pwm9 = 300            # ValueError: 0..255, refused before the wire
    dev.a0 = 1                # AttributeError: read-only, there is no setter
    dev.registers()           # the table the client was generated from
    dev.snapshot()            # every value, one round trip

Without a YAML, the device's own table:

from regtable import RegtableClient, SerialTransport

with RegtableClient.discover(SerialTransport("COM6")) as dev:
    dev.registers()           # whatever the device reports
    dev["led"] = True         # same local checks, by name
    dev["pwm9"] = 300         # ValueError

The client keeps no values; every attribute read is a wire read. The wire carries no request ids, so a timeout or a malformed answer closes the connection rather than pair a late reply with the wrong command; reconnecting re-verifies. Transports are duck-typed: SerialTransport (pyserial), PipeTransport (a CLI process over stdin/stdout), or anything with write_line, read_line, close.

The firmware side, the protocol adapters, and the YAML format are documented in the main repository.