5700A/5720A Series II
Operators Manual
5-52
5-36. Reading the ISR, ISCR, or ISCE
To read the contents of the ISR, send the remote command, ISR?. In a similar fashion, to
read the contents of the ISCR, send ISCR?, and to read the contents of the ISCE, send
ISCE?. The calibrator returns a decimal number representing bits 0 through 15. Every
time you read the ISCR, its contents are zeroed. The following sample program reads all
three registers:
1Ø ! THIS PROGRAM READS THE ISR, ISCR, AND ISCE REGISTERS
2Ø ! Note THAT THE ICSR? COMMAND ALSO CLEARS THE ISCR CONTENTS
3Ø PRINT @4, “ISR?” ! ASK THE ISR CONTENTS
4Ø INPUT @4,A% ! RETRIEVE THE REGISTER CONTENTS FROM THE 57ØØA
5Ø PRINT @4, “ISCR?” ! ASK FOR AND CLEAR THE ISCR CONTENTS
6Ø INPUT @4, B% ! RETRIEVE THE REGISTER CONTENTS FROM THE 57ØØA
7Ø PRINT @4, “ISCE?” ! ASK FOR THE ISCE CONTENTS
8Ø INPUT @4, C% ! RETRIEVE THE REGISTER CONTENTS FROM THE 57ØØA
9Ø PRINT “ISR =“;A% ! DISPLAY THE ISR
1ØØ PRINT “ISCR = “;B% ! DISPLAY THE ISCR
11Ø PRINT “ISCE = “;C% ! DISPLAY THE ISCE
12Ø END
To read the status of the instrument, convert the returned variables into binary. For
example if a register contains 4, its binary equivalent is: 00000000 00000100. Therefore,
bit 3 (EXSNS) is set (1) and the rest of the bits are reset (0).
5-37. Loading the ISCE
By resetting the bits in the ISCE, you can mask (disable) the associated bits in the ISCR.
For example, to cause an SRQ interrupt when an attached 5725A Amplifier turns on, bit
3 (BOOST) in the ISCE register must be 1. (The ISCB bit must also be enabled in the
SRE.) The following sample program loads a decimal 8 into the ISCE, which sets bit 3
and resets the other bits:
1Ø ! THIS PROGRAM LOADS ØØØØØØØØ ØØØØ1ØØØ BINARY INTO THE ISCE
2Ø PRINT @4, “ISCE 8” ! LOAD DECIMAL 8 INTO THE ISCE
3Ø PRINT @4, “ISCE?” ! READ BACK THE VALUE
4Ø INPUT @4, A% ! “
5Ø PRINT “ISCE = “;A% ! PRINT IT, IT SHOULD BE 8
6Ø END