HIFI Cryomag: switch ramp targets and rates mid-ramp

[LilithCole]

As an instrument scientist, I would like the new HIFI Cryomag IOC to automatically change ramp rates past certain thresholds when ramping. When a ramp is specified, the IOC should check the start and end points against the ramp file and construct, then execute, appropriately sloped ramps.

Acceptance criteria:

• [x] When ramps are started, they are split into a series of ramps of the form star point -> [ramp file boundary] * n -> end point
  • [x] All ramps have the apropriate rate at each point of their ramping ~[ ] This would also be the best time to add a change to the emulator where ramp rates do not suddenly change, but gradually change to the correct rate (as seen on real hardware, may need to confirm acceleration rates instrument scientists).~
  • [x] IOC behaves appropriately about zero and for negative fields

[LilithCole]

PRs:

Tests Emulator Support

[John-Holt-Tessella]

Did you need to add code for acceptance criteria:

• This would also be the best time to add a change to the emulator where ramp rates do not suddenly change, but gradually change to the correct rate (as seen on real hardware, may need to confirm acceleration rates instrument scientists).

[John-Holt-Tessella]

• [ ] On my machine OUTPUT is in link invalid alarm. This is still true please fix
• [ ] in lewis log 2020-11-04 17:14:44,397 ERROR lewis.CRYOSMSStreamInterface: Error occurred at GET MID: Precision not allowed in integer format specifier

[John-Holt-Tessella]

Notes for tests:

• set up emmulator.
• monitor camonitor %MYPVPREFIX%CRYOSMS_01:OUTPUT %MYPVPREFIX%CRYOSMS_01:MID:_SP %MYPVPREFIX%CRYOSMS_01:RAMP:RATE:_SP TE:NDW1798:CRYOSMS_01:RAMP:STAT TE:NDW1798:CRYOSMS_01:RAMP:RATE
• set caput %MYPVPREFIX%CRYOSMS_01:MID:SP 4000
• set caput %MYPVPREFIX%CRYOSMS_01:START:SP 1

Rates are in C:\Instrument\Apps\EPICS\support\cryosms\master\ramps\test.txt and are in Tesla