DATED, SEE ELOG14941 for the most up-to-date info on latch.py.

I modified /cvs/cds/caltech/target/c1iscaux/latch.py and /cvs/cds/caltech/target/c1iscaux/C1_ISC-AUX_CM.db to set up the mbbo logic for the other three channels on the CM board, namely REFL2 Gain, AO Gain, and the Super boosts. The systemctl processes were restarted on c1iscaux. We are now ready to perform systematic checks on the CM board functionality.

Remarks:

The addressing of the Acromag BIO registers is done in a way that is kind of inconvenient to use the EPICS mbboDirect protocol

• The control word going to the Acromag is 16 bits in length
• However, only the 4 least significant bits actually correspond to physical channels - the remaining 12 bits are "unused".
• Because each Acromag BIO unit has 16 BIO channels, this means that they are grouped into four "banks" of 4 bits each.
• The mbboDirect EPICS/modbus protocol is used to control multiple physical BIO channels using a single input, which is exactly what we want for the gain sliders on the CM board. However, one caveat is that the bits need to be consecutive.
• This means that we have to break up the 6 bits used for the gain sliders (and in fact also the 2 bits used for the super boosts) into a least-significant-bits (LSB) group and a most-significant-bits (MSB) group.
• What's more annoying is that our physical wiring scheme means that we can't uniformly decide on how this division into LSBs and MSBs work for all the channels - e.g. for REFL1 Gain, the LSB is the 4 least significant bits, while the MSB is the 2 most significant ones, while for REFL2 Gain, the roles are reversed.
• In hindsight, the "clever" way to do the wiring assignment would have been to factor this in - but the problem is (sort of) easily fixed in software, and so I recommend we stick with the existing wiring scheme.

I tested the new latch.py script by toggling the various sliders (one at a time) between two values and monitoring the states of the various soft and "*_BITS" channels, see Attachment #1. The behavior seems consistent to me, but to be sure, we have to use Koji's LED tester board and confirm that the physical bits are being toggled correctly. The StripTool templates live in /cvs/cds/caltech/target/c1iscaux/CMdiag.