I06 Useful GDA commands

Positioning the photon energy

pos selPol 0 (sets horizontal light polarisation)
pos selPol 1 (sets vertical light polarisation)
pos selPol 2 (sets positive circular light polarisation)
pos selPol 3 (sets negative circular light polarisation)

pos iddrpenergy X (200<1400, sets the row phase and gap of the downstream insertion device to X eV)
pos iddenergy X (200<1400, sets the gap of the downstream insertion device to X eV)

pos pgmenergy X (70<2000, sets the included angle of the PGM to give the the energy X eV)

Scanning

scan pgmenergy start finish step counter timeperpoint
e.g scan pgmenergy 700 800 0.1 ca61 1
(scan the pgmenergy from 700eV to 800eV in steps of 0.1eV and count for 1second on the counter channel ca61)

scan pgmenergy start finish step iddenergy start step counter timeperpoint
e.g scan pgmenergy 700 800 0.1 iddenergy 700 0.1 ca61 1
(scan the pgmenergy and downstream insertion device from 700eV to 800eV in steps of 0.1eV and count for 1second on the counter channel ca61)

scan pgmenergy start finish step iddenergy start step uv 1
e.g scan pgmenergy 700 800 0.1 iddenergy 700 0.1 uv 1
(scan the pgmenergy and downstream insertion device from 700eV to 800eV in steps of 0.1eV and acquire a PEEM image for 1 second
Note: this command needs setting up for each different sequence of images which requires the help of the beamline staff for the first time)