[INSTRM-1855] Allow setting an interval between losing line power and shutting down BEE. Created: 04/Feb/23 Updated: 08/Apr/23 Resolved: 07/Apr/23 |
|
| Status: | Done |
| Project: | Instrument control development |
| Component/s: | ics_xcu_pcm |
| Affects Version/s: | None |
| Fix Version/s: | None |
| Type: | Task | Priority: | Normal |
| Reporter: | cloomis | Assignee: | shope |
| Resolution: | Done | Votes: | 0 |
| Labels: | near-term | ||
| Remaining Estimate: | Not Specified | ||
| Time Spent: | Not Specified | ||
| Original Estimate: | Not Specified | ||
| Issue Links: |
|
||||||||
| Sprint: | PreEng11Apr1 | ||||||||
| Description |
|
The PCM has a mechanism for powering off ports based on input voltage, which is used to power down all but the components required to run the detector heater. This currently detects the clear switch from line power to battery power. It also detects dropping below a voltage which indicates that the batteries are getting exhausted. The current logic uses those to decide when to power off the BEE, etc. We would like a variant on that. Define the switch from line to battery power as t0. After a configurable interval from t0, if line power has not been restored, power off the BEE, etc. The BEE can independently mark t0, or at least a decent proxy for that. So it will know when its power will be cut off and thus be able to shut itself down properly or do any other cleanup tasks. |
| Comments |
| Comment by cloomis [ 08/Mar/23 ] |
|
We realized that the PCM could use its second supply to trigger the shutdown, which is directly connected to line power: that supply will go from ~24V to 0V immediately, and we do not need to be clever about LiFePO4 internals. Hope is changing the PCM routine to do that. |
| Comment by cloomis [ 07/Apr/23 ] |
|
This has been done and tested on SN3 at JHU. PCM Version 20230310-01 SN2,SN3,SN4 have been upgraded. Will negotiate wth fmadec about upgrading SN1 at LAM. Oh. We did not use the direct supply, since that is back-fed by the turbo when that spins down. Too confusing to use. |
| Comment by fmadec [ 07/Apr/23 ] |
|
no problem for me. Can that update be done while camera is cold ? |
| Comment by cloomis [ 08/Apr/23 ] |
|
Updating the PCM firmware power-cycles everything including the BEE. So we should wait until nir-sn2 is warm. |