MockSOLO.jl

A mock Sutter SOLO-50 single-axis micromanipulator for testing host software without hardware. MockSOLO serves the SOLO's serial protocol (Operation Manual Rev. 1.09b, chapter 4) on a virtual serial port (a POSIX pty). Anything that can open a serial port, such as pyserial, can talk to it as if it were the real controller.

Realistic timing. Moves run at the real 3000 µm/s, and the end-of-move CR arrives when the move finishes. Use timescale to speed this up in tests.
Front panel. From Julia you can press HOME, WORK, PULSE and the other buttons, turn the knob, and read the screen, as a person at the controller would.
Traffic log. Every byte in each direction is recorded with a timestamp.

macOS and Linux only.

AI disclosure

Most of this package was written by Claude (Anthropic's AI model) using Claude Code: the code, tests and documentation. The author directed and reviewed the work. Treat it as you would any young, lightly tested package.

Install

MockSOLO is not registered. Install it from a local clone:

using Pkg
Pkg.develop(path = "/path/to/MockSOLO")

or with Pkg.add(url = ...) and the repository URL once it is hosted.

Quick start

using MockSOLO

dev = MockSOLO.start(timescale = 100)    # moves run 100× faster; Inf = instant
portname(dev)                            # e.g. "/dev/ttys004", give this to a host

host = open_port(portname(dev))          # host side, in this same process
write(host, UInt8('c'))                  # ask for the position
r = read(host, 5)                        # 4 bytes, least-significant first, then CR
ltoh(only(reinterpret(UInt32, r[1:4])))  # 0x000029ab == 10667 µsteps = 1000 µm

write(host, UInt8('x'), htol(UInt32(20_000)))  # move to 20,000 µsteps
read(host, 1)                            # CR arrives when the move is done
position_usteps(dev)                     # 0x00004e20 == 20000

traffic(dev)                             # every byte exchanged, timestamped
close(host)
stop(dev)

Use `open_port` in the same process

The mock runs as tasks inside your Julia process. Blocking I/O on the port, such as open(path), an IOStream or ccall reads, stops those tasks from running and hangs. External programs can open the port however they like.

Where next

Host software covers driving the mock from Python or another program.
Protocol is the byte-level command reference and what the mock does where the manual is silent.
Front panel simulates a person at the controller.
Limitations lists what a pty can't do.
API reference documents every function.