Serial Port Debug

This is a temporary page for fault finding with changes from https://github.com/ISISComputingGroup/IBEX/issues/4435

symptoms: com port stuck, no reads work, dbior hangs.

Until this PR is deployed you will first need to update asyn.dll for the IOC concerned

• stop IOC concerned
• copy asyn.dll from Ticket4435 build (asyn_ovio jenkins job) to same directory as .exe for IOC (so it will load in preference to existing asyn.dll)
• start IOC
• when done, remove new asyn.dll from the IOC bin/windows-x64 directory

After restarting with new asyn you should be able to type

dbior drvAsyn 5

without it hanging. The new ASIO may even fix the issue, but should at least give you more output. If the IOC is not fixed, can you try adding:

epicsEnvSet("WAITFORBYTES",1)

to the st.cmd, this will enable another sort of read mode to test.

It would also be worth adding

asynSetOption("L0", -1, "eventmask", "0x11b")	

to startup, this will print all com events except writes – to see writes too use:

asynSetOption("L0", -1, "eventmask", "0x11f")

You can also stop IOC and try using the testSerialPort command https://github.com/ISISComputingGroup/ibex_developers_manual/wiki/TestSerialPort

It is also possible to use the new "escape" and "purge" options with asynSetOption at runtime to manipulate the various things about the send and receive buffers and line status.