[Swreq] Request for EPICS readout from device in MCC equipment room

[tiefen at jlab.org]

The device is a Stanford Research Systems SR620, a frequency counter
installed in the Master Oscillator rack.  An online link (currently valid)
to a manual for this device is:

http://www2.rohde-schwarz.com/file_8022/manual_SR620m.pdf

The device is controllable via RS232 and GPIB/HPIB, and I only need
readback of the frequency once the device is configured to read the 499
MHz frequency.  I copy this to Musson & Plawski in case they have other
functions they wish to add to this request.  It would be convenient to
have the device auto-configure to the appropriate state for reading 499
MHz upon initialization.  Please make this at least selectable, for the
sake of convenience, but it is not REQUIRED given the close proximity of
the Control Room to the Equipment Room.

The functionality I would require is:
1) a remote "INIT" function to make the EPICS system connect to the device
2) ability to read back frequency at least as often as every 5 seconds.

It would be preferred to have a user-selectable rate at intervals of down
to 1 second for special cases, but a fixed update rate of 5 seconds is
acceptable.    There are "gating" and "arming" actions required to make
the device sample data, and I will have to gather the information to
provide to support the configuration.

This request is part of support for the 12 GeV path to frequency
compensation for path length control.

Michael Tiefenback