CAEN V830

 

Force a trigger

The models V820 and V830 are 1-unit wide VME 6U Latching Scaler and Multi-event Latching Scaler modules, housing 32 independent counting channels. Each channel has 32 bit counting depth and accepts either ECL or LVDS inputs, depending on the purchased version, a TTL version is available on request; the maximum input frequency is 250 Mhz.


The counters’ values can be read “on the fly” from VME without interfering on data acquisition process. The model V830 is equipped with a 32 kwords multievent buffer (MEB) memory which may be used to store and readout accumulated data during subsequent counting.


The TRIGGER signal can be provided by an external NIM/ECL signal or by a VME request. It’s also possible to generate a periodical trigger signal by means of an internal programmable timer.


Please refer to the v830.pdf for more details.

 

There are two types of records produced by this object, a polled read of the counters, and triggered events.


Polled Counter Record format


xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx

^^^^ ^^^^ ^^^^ ^^----------------------- V830 ID (from header)

-----------------^^ ^^^^ ^^^^ ^^^^ ^^^^- length (always 20 longs)

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx

--------^-^^^--------------------------- Crate number

-------------^-^^^^--------------------- Card number

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx  enabled mask

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx  UT time of last read

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx  counter 0

..

..

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx  counter 31


Triggered Event Record format


xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx

^^^^ ^^^^ ^^^^ ^^----------------------- V830 ID (from header)

-----------------^^ ^^^^ ^^^^ ^^^^ ^^^^- length (variable)

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx

--------^-^^^--------------------------- Crate number

-------------^-^^^^--------------------- Card number

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx  Channel 0 roll over count

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx

-------------------------------------^^- Acq Mode. 0=disabled,1=Random, 2=periodic

------------------------------------^---- Data Format 0=32Bit,1=24Bit

-----------------------------------^----- Header Enabled (always set)

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx   Enabled Mask

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx   counter 0 or header (if header, then chan0 follows)

..

..

xxxx xxxx xxxx xxxx xxxx xxxx xxxx xxxx  counter 31


Note that only enabled channels are included so list may be shorter than 32 counter values. Also note that the header may or may not be included based on the ‘Include Header’ option.



Set the VME Address

The write value to use

Operation to do on the selected register using the current set of values

Extra Info about the selected register

The card’s register list. the current operation will be applied to he selected register. See the documentation that came with the card for more information on each register

Trigger mode can be ‘Disabled’, ‘Random’, or ‘Periodic”.  Periodic uses the Dwell time for an internal trigger generation.

Set to 32 or 24 bit format

Reset counters after trigger.

Clear buffer on front panel clear signal

Period of internal trigger -- use with the ‘Periodic’ trigger mode

Load dialog settings to HW

Read and print counters to status log

Resets most regs -- see manual for exceptions

Ship counter values after a poll -if- run in progress

Resets counters, temp buffers, MEB, registers, etc