camac - Generic CAMAC Record

Contents

• Overview
• Field Descriptions
• Files
• Release Notes
• Example

Overview

The CAMAC record is designed to perform generic CAMAC I/O. The CAMAC Branch (B), Crate (C), Slot (N), Subaddress (A), Function code (F) and transfer mode are all controlled by record fields which can be modified at run time. Applications for this record include accessing CAMAC modules for which no device support exists, and for performing CAMAC diagnostics.

The CAMAC record is intended only for this specialized CAMAC I/O function. The CAMAC record directly calls the ESONE compatible CAMAC library, without an intermediate device support layer.

The CAMAC record supports array operations, i.e. CAMAC block transfer operations. The VAL field contains the data to be written or the data read. Depending upon the CAMAC hardware being used this may use DMA from the CAMAC controller to the VME bus memory.

This record requires the use of an underlying ESONE compatible CAMAC library. A library which supports serial highway drivers and the Kinetic Systems 2917/3922 parallel bus crate controller is now available. This library should be available as an EPICS extension in the near future.

If a CAMAC operation returns Q=0 it will be reflected in the Q field of the record, but will not raise an alarm. X=0 will raise a minor alarm. Any other errors detected in the CAMAC library will raise a major alarm.

Files

The following table briefly describes all of the files required to implement the CAMAC record. The reader is assumed to be familiar with the EPICS Application Source/Release Control document which describes how to build an EPICS application tree into which these files are to be placed, and how to run "makesdr" and "gnumake" to build the record support. These files can all be obtained in a compressed tar file. This file should be untarred in a <top>/<app>App/ directory.

CAMAC_SRCS      = ../recCamac.c

SRCS.c = $(CAMAC_SRCS) $(other sources here)
CAMAC_OBJS       = recCamac.o
LIBNAME = mylib.o
LIBOBJS = $(CAMAC_OBJS) $(other objects here)

USR_CFLAGS = -I$(EPICS)/replace_ascii -I$(EPICS)/cat_ascii \
             -I$(EPICS)/sdrH/rec -I$(EPICS)/include/rec \
             -I$(EPICS_EXTENSIONS_INCLUDE)

#include <choiceRecCAMAC.ascii>

"camac"

cars1> medm -x -macro REC=my_camac_record CAMAC_IO.adl

---

Release Notes

• Version 1.0, March 1996, Mark Rivers, Initial Release
• Version 1.1, December 1997, Time Mooney, Conversion to R3.13

Example

The following IDL program demonstrates the use of the Generic CAMAC record. It does a block-mode read of a scaler in slot 14 and plots the results. It also demonstrates using the "Crate Command" (CCMD) field to clear the Inhibit line.

; This IDL program demonstrates the use of the 
; Generic CAMAC record. 
; It does a Q-repeat read of a scaler in slot 14 
; and plots the results.

; The name of the generic CAMAC record
rec = 'test_camac1'

; Set up B, C, N, A for scaler 0 (first scaler)
;   in slot 14 on crate 0, branch 0.
t = caput(rec+'.B', 0)
t = caput(rec+'.C', 0)
t = caput(rec+'.N', 14)
t = caput(rec+'.A', 0)

; Make sure the crate Inhibit line is clear, 
;   because it would stop the scaler
t = caput(rec+'.CCMD', "Clear Inhibit")

; Set the transfer mode to Q-repeat
t = caput(rec+'.TMOD', "Q Repeat")

; Set up to read the scaler 1024 times
t = caput(rec+'.NUSE', 1024)

; Read the scaler into the record VAL field
;   by forcing the record to process
t = caput(rec+'.PROC', 1)

; Make sure we got the number of values we expected
t = caget(rec+'.NACT', nact)
if (nact eq 1024) then $
    print, 'Read CAMAC scaler OK' $
else $
    print, 'Error reading CAMAC scaler'

; Read the data into IDL - only valid data
t = caget(rec, data, max=nact)

; Plot the data
plot, data

end