Consider adding a ValveState register to set the state of all valves simultaneously.

[RoboDoig]

Currently, there are separate state registers for odor valves and end valves (71, 72). The separation makes sense in the case where these valve sets have clearly defined roles.

In some cases however these roles can be less clear, for example where two olfactometers are being used as 1 device (to expand odor panel) one of the end valve sets may be used to switch between odor manifolds from the two respective olfactometers.

Given this use case, and also to achieve symmetry across registers/devices, it would be nice to have a ValveState register (ValveSet, ValveClear, ValveToggle, ValveState) where a user can set the state of all valves simultaneously. Should also not require too much firmware alteration since the odor valve and end valve masks have non-overlapping bits.

[bruno-f-cruz]

After discussing this with @RoboDoig something else came to mind regarding analysis. If the state of the valves is simultaneously represented by two registers, it may be possible that users need to do a fair amount of post-processing to construct the full state of the board. At a bare minimum, reads to these registers should return synchronized information by accessing a common private value.

I am starting to agree with @Poofjunior on her suggestion harp-tech/protocol#30 as it would make this pattern fully composable. Probably worth discussing this again during an upcoming club.