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Here the CompTH_ePixM register defines the location of the switching point. The values of these registers are subject to change as we start to characterize the detector and might change a bit when we optimize the performance. So, for a pedestal script, we would likely want to cycle through these settings and collect ~2000 frames in each cycle to determine their relative pedestal maps (AHL, SH,SM).

From Dionisio:  Speaking with Lorenzo, the Precharge_DAC changes with the pixel mode. So it does not get to be scanned but it is set intentionally at the same time as the threshold is set.  Here (https://confluence.slac.stanford.edu/display/ppareg/ePixM%3A+gain+modes) are some suggested values.

For the charge injection, that is also a new beast for this detector. Unlike the previous detectors, we are not injecting an external signal, but switching an already charged capacitor. This has been implemented in a way that charge injection occurs for all pixels in column in one go. I talked to Dionisio and Lorenzo and they will ask Dawood to provide some documentation on how you make charge injection happen for this detector. Also, unlike the previous detectors where we performed charge injection on a central pixel, with no charge injection on its neighbor, and then cycled through all pixels so they all receive charge injection, here we will be performing charge injection on a combination of columns simultaneously and stepping through, but Dionisio and Lorenzo wanted to cycle around how to do this and then get back to you.

See Charge injection with python using helper functions.

From Chris: I think for previous detectors charge injection has run in all modes.  The actual settings will be tweaked, but it would be good to do the same for epixM, and ideally verify that the pixels do change range when the switching threshold is set somewhere in the middle.

From Dawood: I talked to Lorenzo. Yes, the columns need to be reprogrammed everytime. Meaning that you would need to run the prepareChargeInjection everytime before running a trigger event, even if the columns configuration does not change between the two consecutive trigger events.