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Each group of elements will be broken into sections for better comprehension:

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ADJUST_INT_WINDOW ADJUST_INT_WINDOW

Adjustment of the integration windows

The system provides a way to adjust 3 regions for the signal. The leftmost region, shown as "Duration pre edge (ns)" on the picture below, integrates the background noise to be subtracted from the signal region. The rightmost region, shown as "Duration pos edge (ns)" on the picture below, integrates the signal. An optional "Duration inter edges (ns)" defines a region between the background noise and the signal where the integration is ignored. It is useful for removing the slope from the calculation. This middle region is not shown in the chart below.

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The next step is to provide PVs for the user to change the pre, inter, and post edges windows in nanoseconds and convert them back to tick counts. This step is more tricky because the firmware does not accept odd numbers. The user changes the PVs TIME_PRE, TIME_MID, and TIME_POS and calc records convert it to tick counts, writing the value to the firmware through the records NumSamp0, NumSamp1, and TrigDelay1.

To convert from nanoseconds to tick counts we need the AMC clock frequency, as before, multiply by the number of nanoseconds and divide by 1 billion, as the clock frequency is taken as Hz. Also, the clock frequency informed by the firmware is half of what is real, so we need to multiply everything by 2. This is what gives us the equation 2*A*B/1000000000. This number is rounded with the FLOOR operator, that can generate an odd number. The firmware expects only even numbers, so we need to guarantee that the LSB is always zero by doing an AND with the result and ((~0)-1).  ~0 gives all "1" for all the bits. Subtracting 1 gives us all bits "1" besides the last one.

The inter-edges window must be divided by 2 per firmware requirement. Also, we are guaranteeing that the size of the inter-edge window is never lower than the pre-edge window for the reason explained before in Adjustment of the integration windows. That's the function of the record TIME_MIDC.

The firmware registers for these records are the same as described before, as you can see by the OUT field with the Asyn parameter name.

The last feature provided by the weightFunctionXAxis.db is to generate an array for the X-axis of the chart, containing the translation to nanosecond for each tick count. This is held by the aSub record BLEN:$(AREA):$(POS):$(INST)_WF_TIME, using the function calcTimeArray() available in the file asubWeightXAxis.c. The input for the record is the PV AmcClkFreq already described before.