Cryogenics: API

The MUSCAT Cryogenics Control and Logging (MC-CAL) software provides a basic API which allows users to collect key information about the current state of the cooling platform from other applications. This is designed for on-site use and only provides communication over the local network and not internet wide.

Interface

The MC-CAL API runs via UDP communication. Sending a UDP packet to the machine running MC-CAL on port 3002 containing one of following queries will result in MC-CAL replying on the same port with the relevant data. No reply is sent on other ports or to unrecognised quires. Queries are case insensitive. Each reply will start with a unix timestamp followed by the relevant information. Replies are comma delimited.

Query Options

Query	Description	Example Reply (truncated)
getTemps, gt, t	Returns a list of the current temperature values	1587558515.12,293.9883,294.5592,294.5081,...
getRaw, gr, r	Returns a list of the raw (uncalibrated) sensor measurements	1587560365.83,0.581563,0.580301,0.580414,...
getChannelNames, getChannels, gc	Returns a list of descriptive channel names in the same order as the output of getTemps and getRaw	1587558550.16,50-K PTC,50-K Plate,50-K Lid,...
getStatus, gs	Returns a description of the current state of the sorption refrigerator recycling	1587558482.77,A - Waiting to condense He4. 00:07:44 left.
numDiodes nd	Returns the number of diode temperature sensors at the start of the list returned by getTemp	1587559678.05,20
numRTDs, nRTD	Returns the number of RTD temperature sensors at the end of the list returned by getTemp	1587559193.73,12

Minimal Example

The following is a minimal working example of a Python script to query MC-CAL and print the response to the terminal.

import socket

HOST = '10.73.2.178'
PORT = 3002

# Set up UDP (SOCK_DGRAM) socket
sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.settimeout(2)  # Timeout in seconds


def MCCAL_query(qry):
    try:
        sock.sendto(qry.encode(), (HOST, PORT))  # .encode to convert to bytes
        reply = sock.recv(1024)  # Max buffer size = 131072 B
        if reply:
            print(reply)
    except socket.timeout:
        print('Timed Out')

Using the above code, calling MCCAL_query('getTemps') would give a reply of the form b'1587558895.68,293.9883,294.5592,294.5081,294.8287,294.0846,294.7323,294.4380,301.1023,300.6758,300.6543,301.0906,293.9906,301.0401,300.6281,301.0296,300.5700,300.9584,300.5541,300.5486,300.5172,300.0000,300.0000,300.0000,300.0000,300.0000,8.0579,6.2537,300.0000,300.0000,300.0000,300.0000,4.6586'