Additional Staff Info
  CV2100 Camera based interlock
Durring fully atomated opperations it is necceary to be able to determin the location of the sample mouting magnet at fairly high speed and with a good degree of precision. It is also neccary to determin the presence of a sample, and lastaly it is highly desireable to know if frosting is present on the sample.

We have made use of a small set of the CV2100s functions in recording the state of the sample mounting. Each of a series of windows or regions of intrest are examined by the unit and compared to set of bounding conditions produceing a good/no-good responce. The responce from a triggering of the unit is then retrived over a TCP/IP interface by an EPICS IOC oppertating under Linux.

The result of the windows are interperted by a Multi Bit Binary Input(MBBI) record capable of evaluating 16 states. The results from the CV2100 are coded in to a single intager number by:
W1*2**0 + W2*2**1 + W3*2**2 +....WN*2**N-1 where W1 is the first window evaluated by the CV2100.

The cv2100 and the epics mbbi record can be configured by the beamline staff to evaluate the correct conditions at there beamline with out any need for new functional code.

An example record in use at X29: 

 
record(mbbi,"$(P)Cam:MBBI"){
    field(DESC, "MBBI test")
    field(PINI, "1")
    field(SCAN, "10 second")
    field(DTYP, "CV2100")
    field(INP,  "#L$(L) A$(A) @")
    field(THST, "Safe Mount")
    field(THVL, "15")
    field(ONST, "Safe Umount")
    field(ONVL, "14")
    field(TWST, "Frost")
    field(TWVL, "30")
    field(ZRST, "ERROR")
    field(ZRVL, "0")
    field(ZRSV, "MAJOR")
}

The full Device support code used to can be found here under our source control system.

Updated 16 Dec 2005 Security Notice   Webteam   Site Map   Bio   PXRR   NSLS   BNL