serialio 0.1.1

Concurrency agnostic serialio API

serialio

![Pypi version][pypi]

A python concurrency agnostic serial line library.

Helpful when handling with instrumentation which work over serial line and implement simple REQ-REP communication protocols (example: SCPI).

So far, only serial line over RFC2217 protocol and raw socket are available. It should be compatible with:

• ser2net bridge with telnet and raw configurations
• gserial[ser2tcp] bridge (RFC2217)

Base implementation written in asyncio with support for different concurrency models:

• asyncio
• classic blocking API (TODO)
• future based API (TODO)

Here is a summary of what is forseen and what is implemented

Concurrency	Local	RFC2217	Raw TCP
asyncio	N	Y	Y
classic sync	N	N	N
conc. futures	N	N	N

Installation

From within your favourite python environment:

pip install serialio

Usage

asyncio

import asyncio
from serialio.aio.tcp import Serial

async def main():
    sl = Serial('raw.ser2net.com', 5000)
    # Assuming a SCPI complient on the other end we can ask for:
    reply = await sl.write_readline(b'*IDN?\n')
    print(reply)

asyncio.run(main())

classic (TODO)

from serialio.sio.tcp import Serial

sl = Serial('raw.ser2net.com', 5000)
reply = sl.write_readline(b'*IDN?\n')
print(reply)

concurrent.futures (TODO)

from serialio.sio.tcp import Serial

sl = Serial('raw.ser2net.com', 5000, resolve_futures=False)
reply = sl.write_readline(b'*IDN?\n').result()
print(reply)

Features

The main goal of a serialio Serial object is to facilitate communication with instruments connected to a serial line.

The most frequent cases include instruments which expect a REQ/REP semantics with ASCII protocols like SCPI. In these cases most commands translate in small packets being exchanged between the host and the instrument. When a raw TCP or RFC2217 bridge is used to access the serial line, serialio uses the sockio library.

REQ-REP semantics

Many instruments out there have a Request-Reply protocol. A serialio Serial provides helpfull write_read family of methods which simplify communication with these instruments.

Auto-reconnection

TODO: Write this chapter

Custom EOL

In line based protocols, sometimes people decide \n is not a good EOL character. A serialio can be customized with a different EOL character. Example:

sl = Serial('raw.ser2net.com', 5000, eol=b'\r')

The EOL character can be overwritten in any of the readline methods. Example:

await sl.write_readline(b'*IDN?\n', eol=b'\r')

Streams

TODO: Write this chapter