Overview

PyHK is a suite of Python software developed to collect, store, and view cryogenic housekeeping data and to control heaters and fridges. It is developed with the intention of being flexible and extensible, allowing differing hardware configurations to be managed by the same platform. Versions of the code have been in use since 2014, and it is still in active development. PyHK is made of several separate packages, of which the main few are described below.

  • pyhkd is the main instrument control sofware, which runs indefinitely collecting data and storing it to files /data/hk. It is designed to run in the background as a system service, but can also be explicitly executed in a terminal. pyhkd listens for command packets and execute valid requests (setting a voltage, etc.)

  • pyhkweb is a web viewer that is used in conjunction with Apache. It is the primary method for monitoring and controlling housekeeping and fridge scripts, even on the local machine. Once installed it is started automatically by Apache as needed, you never need to run pyhkweb.py yourself. You should have a DNS name (typically __.pyhk.net) assigned to your machine, and you use that name to access the website. If you are running in a situation with no internet access, you can still access pyhkweb locally at http://127.0.0.1.

  • pyhkfridge is responsible for the fridge cycle and other related scripts (like automated G measurement or heating the pumps during cooldown). It watches the files in /data/hk for changes and issues commands to pyhkd via sockets. An arbitrary number of instances of pyhkfridge can be run simultaneously. pyhkfridge is designed to run in the background as a system service and controlled via pyhkweb.

  • pyhkcmd (still in development) is a command line interface script for PyHK. While pyhkfridge is the preferred method for writing scripts the read or write PyHK data (due to its integeration with pyhkweb), pyhkcmd may be easier to integrate into exisiting workflows.