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Task #17724

Milestone #17719: Booster operational test of one crate alongside existing BPM system

Task #17720: Booster BPM ACNET Interface

ACNET device BPM Turn-by-Turn Scaled Positon

Added by John Diamond almost 2 years ago. Updated almost 2 years ago.

Status:
Work in progress
Priority:
Normal
Assignee:
John Diamond
Start date:
09/15/2017
Due date:
% Done:

90%

Estimated time:
4.00 h
Spent time:
5.50 h
Duration:

Description

Implement Booster BPM ACNET device 0x0015

History

#1 Updated by John Diamond almost 2 years ago

  • Status changed from Assigned to Work in progress

#2 Updated by John Diamond almost 2 years ago

  • % Done changed from 0 to 70
  • Estimated time set to 4.00 h
Developed a device for returning positions from the most recent turn-by-turn measurement according to the specification given for the existing Booster BPM system. A couple of things need to be resolved still:
  • The 'data' and 'time' fields are specified as 'Int4' fields but it's not clear what this really means. Will need clarification from Bill Marsh. For now these fields return '0' and '1' respectively.
  • Not clear to me what the 'cycle_type' field is meant to contain. For now it always returns '4'.
  • The maximum number of positions we can return (as 4-byte floats) is 8187 (TBT_POSITION_ARRAY_SIZE). Will need clarification from Bill Marsh how the existing system returns the full 20000 turns. Note that the n_samples field contains the actual number of samples contained in the measurement and can be > 8187.
  • This device was specified with no reading PDB and an element size of 1, which means that the console application is probably expecting big-endian data but we are returning little-endian data because the BBPMTS processor is an x86.
Created a test device on BBPMTS:
  • Z:VTS900

Control and Basic Status properties still need to be implemented.

#3 Updated by John Diamond almost 2 years ago

  • % Done changed from 70 to 60

Excerpt of an e-mail from Bill that mentions undocumented fields in the TBT header:

For the turn by turn data Sharon seems to not have documented the 
inclusion of the GPS timestamp  The data structure is as follows
Int4 micro date
Int4 micro timestamp
Int4 GPS sec (UTC time)
Int4 GPS nsec (nanosec from GPS sec)
Int4 number of turns
Int4 cycle type
Flt4 turn position data
Again  the positions data ieee floats are word swapped but not byte
swapped while the header data is used as is.

The full e-mail, which describes endianess and timestamp encoding is documented in #17720.

#4 Updated by John Diamond almost 2 years ago

  • % Done changed from 60 to 80

Filled in the missing fields per Bill's e-mail. Also added the gps time stamp fields to the device. Did not test yet.

#5 Updated by John Diamond almost 2 years ago

GPS time fields look correct. Implemented basic status and control properties but all these do is toggle an internal variable for now. They will need to be attached to the Booster BPM state machine once it is implemented.

#6 Updated by John Diamond almost 2 years ago

  • % Done changed from 80 to 90

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