J. Kissel, D. Barker

I've done several things to investigate the problems recently been seen with the binary switching of the H1 SUS ETMX L3 ESD LV/HV driver system (see FRS Ticket 6527, LHO aLOG 30879, LHO aLOG 30770).

1) I've toggled all of the relevant channels,
H1:SUS-ETMX_BIO_L3_[UL,LL,UR,LR]_VOLTAGE_SW
H1:SUS-ETMX_BIO_L3_[UL,LL,UR,LR]_HVDISCONNECT_SW
and confirmed that they are monitored in the 
/opt/rtcds/userapps/release/sus/h1/burtfiles/h1susetmx_down.snap
and they show up as DIFFs when toggled to the wrong state for high-voltage actuation.

2) I've confirmed that where the front end looks for safe.snap and down.snaps,
/opt/rtcds/lho/h1/target/h1susetmx/h1susetmxepics/burt/
lrwxrwxrwx 1 controls controls     64 Apr 27 12:23 down.snap -> /opt/rtcds/userapps/release/sus/h1/burtfiles/h1susetmx_down.snap
lrwxrwxrwx 1 controls controls     64 Jul 19 19:22 safe.snap -> /opt/rtcds/userapps/release/sus/h1/burtfiles/h1susetmx_down.snap
are pointing to the same down.snap reference file.

3) With the help of Dave, I've restarted the front end process for h1susetmx, and confirmed that upon reboot, the front end restores to 
lrwxrwxrwx 1 controls controls     64 Jul 19 19:22 safe.snap -> /opt/rtcds/userapps/release/sus/h1/burtfiles/h1susetmx_down.snap
and it restores correctly to the high-voltage configuration.

4) I've looked at the list time the down.snap file was changed, 
-rw-rw-r-- 1 jeffrey.kissel controls 103354 Oct 25 12:43 h1susetmx_down.snap
(that's Oct 25 12:43 PDT) and it was yesterday, when I was removing the ISIWIT channels from the reference files (as mentioned in LHO aLOG 30844)
so it's not as though these settings *were* wrong the last three reboots when there *was* a problem, and then yesterday Sheila (after I'd left for the day and found the problem) modified the down.snap to have the correct values.

5) I've checked the ISC_LOCK guardian for instances of "BIO_L3" looking for any incorrect guardian toggling of these switches, and found that only the DOWN and LOW_NOISE_ETMY states toggle those switches. The DOWN state correctly toggles the switches to high-voltage actuation, and the LOW_NOISE_ETMY state correctly toggles the switches to disconnect the high-voltage. In fact I grepped all guardian code that lives in /opt/rtcds/userapps/release/isc/h1/guardian and /opt/rtcds/userapps/release/sus/h1/guardian, and found that no other guardian touches these channels.

6) Since ISC_LOCK toggling uses guardian infrastructure that commands the switching with 1s and 0s instead of ONs and OFFs, I confirmed via the command line with good ol' "caget" and "caput" that what the guardian sends the correct commands.

In summary -- No Dice. I was not able to reproduce Sheila's problems, upon reboot the switches come up in the right state, and just in case the ISC_LOCK guardian forces the switches to be in the right state. The problem that Sheila and Ed saw should not have occured.

I have no choice but to throw up my hands and close the FRS ticket. Sorry!