source: trunk/FACT++/ScriptsForDimCtrl/FeedbackOn.dim

#!dimctrl --exec

# dimctrl script
>
> -------------------------------------------
> Bias and Feedback StartUp (Current Calibration)
> -------------------------------------------

.w 2000
# As a First step we want to calibrate the current, which are read from the bias crate,
# and not take a DRS calibration, as it is mentioned in the data taking page...
# so for this we should get the feedback and biasctrl programs into known states
# I think it is good to try a RECONNECT to the bias, and make sure the voltage is off
#
# NOTE:
# The ideas in the line above are both valid, but both not done.
# This is *not good*

# Since we do not know, what the feedback program is doing at the moment, we should as well,
# tell it to keep its mouth shut ... just to be sure, we know whats going on
> stopping feedback
FEEDBACK/STOP
.w 2000
# stopping should always be possible, and end in state 'Connected'(6)
.s FEEDBACK 6
> ..done

#BIAS_CONTROL/RECONNECT
# If we were disconnected, and this was the first try of the night, the bias_ctrl should
# be in state 'VoltageOff'(7) more or less immediately
#.s BIAS_CONTROL 3
#.s BIAS_CONTROL 7 5000
# if these assumptions are all wrong, then we might have been properly connected anyway,
# and just have to ramp down... lets do it, but wait forever, in case it does not work
> switching off bias
BIAS_CONTROL/SET_ZERO_VOLTAGE
.w 2000
.s BIAS_CONTROL 7
> ...done

# in case we reach this line, the voltages are all off, and the feedback does not do anything
# So lets do the current calibration, therefor we tell the bias crate to ramp up just 1 single DAC count(~22mV)
# the result of this action is, to get bias_ctrl into the state 'VoltageOn'(9), but since we only go one DAC count it shouldn't take long
> setting bias globally to 1 DAC
BIAS_CONTROL/SET_GLOBAL_DAC 1
.w 2000
.s BIAS_CONTROL 9
> ...done

# now we may tell the feedback program to calibrate the currents ...
# I do not understand, if I have to explicitely allow the feedback program to generate output,
# or if it just produces output...
# As far as I understand, the feedback output enable status is the same,
# as it was before I send the STOP command... so it is unknown at this point.
# and in addition enabling or disabling the output, when STOPed is not possible as far as I know...
# I try to enable it anyway.
> enabling output for feedback
FEEDBACK/ENABLE_OUTPUT yes
.w 2000
> ...done

> calibrating bias crate current readings...
FEEDBACK/CALIBRATE_CURRENTS
.w 5000
# in order to find out when the calibration ends, we have to wait for the transistion from state
# 'Calibrating'(13) back to 'Connected'(6)
.s FEEDBACK 13
.s FEEDBACK 6

# Thomas Bretz told me, that the feedback, after this step has disabled its output
# and is in the mode, we might call 'temperature control' even there is no temerature beeing controlled.
# I don't know where the voltage is ... in order to perform the calibration, the feedback had to
# ramp up to 2V below the operational voltage, i.e. about 1V below the breakdown voltage

# We want to take a DRS amplitude calibration so we have to ramp down the bias voltage.
# this 10sec wait is needed in order for the bias not to disconect all the time...
> ... current calibration done
.w 10000

> switching off bias
BIAS_CONTROL/SET_ZERO_VOLTAGE
.w 5000
.s BIAS_CONTROL 7
> ...done

# now we want to take a run, with dark counts events
# so we need to ramp up the voltage
# we want to use the 'current control' more so we give the commands for this...
> switching on current controll feedback ...
FEEDBACK/STOP
FEEDBACK/START_CURRENT_CONTROL 0.0
FEEDBACK/ENABLE_OUTPUT yes
# the feedback should be in state 'CurrentControl'(12) now
.s FEEDBACK 12
> ... done
> switching on bias
# now we give the feedback a hint, that it may ramp ...
BIAS_CONTROL/SET_GLOBAL_DAC 1
# after this command the bias_ctrl should be in state 'VoltageOn'(9) after a second or so
.s BIAS_CONTROL 9
> ...1 DAC globally set
# then usually it takes some time until the feedback has enough information to really start controlling the voltage
# when the feedback actually kicks in, the bias is first in state 'Ramping'(5) for some seconds and finally in 'VoltageOn'(9)
# again
.s BIAS_CONTROL 5
> ...ramping to nominal voltage
.s BIAS_CONTROL 9
> ...bias on
# here we should wait 45 sec in order for the current control to get enough current readings and temp readings to stabilize..
> waiting 45sec for the current control to stabilize...
.w 45000
> ... done


# at the end the bias voltage should be ramped down, since in a few seconds a shifter wit ha flashlight
# will come out to open the shutter...
> switching OFF bias ...
BIAS_CONTROL/SET_ZERO_VOLTAGE
.s BIAS_CONTROL 7
> ...done
> ----------------------------------------------------
> Bias and Feedback StartUp (Current Calibration)
> ... done.
> ----------------------------------------------------
>