HP 8153A - Page 253

Using the FETCh Command - An Example
This example is a subroutine to take a reading from the second channel of the
power meter. The original program, as written for the HP 8162A is given on the
left. The modified program, to run on the HP 8153A (in HP8162A Compatability
mode), is given on the right.
Old Program (IIP8153A)
1300 SUB Singlc'meas{P$)
!310 CLEAR Rmm
1320 OUTPUT Piiini;”CSB"
1330 OUTPUT Pmm;”WVL 2,130iNM;M2;CH2;UI;Tl;ARl
1340 TRIGGER Pinm
1360 S»-SPOLL(Pmm)
1360 IF BlT(S,2)-0 THEN GOTO 1360
1370 ENTER Piinn;P«
1380 OUTPUT Pmm;”CSB'’
1390 IX)CAL Pmm
1400 SUBEND
Now Program (HP 81B3A)
1300 SUB SlngIe'meaa(P4)
1310 CLEAR Pmin
1320 OUTPUT Pmm;”CSB”
1330 OUTPUT PmmC’WVL 2,1301NM;M2;CH2;U1;T1;AR1”
1340 TRIGGER Pmm
1360S=SPOLL(Pmm)
1360 IF BIT{S,2)~0 THEN GOTO 1350
1366 OUTPUT Pmm;”FETC:POW?"
1370 ENTER Pmm;PS
1380 OUTPUT Ptnm;”CSB”
1390 LOCAL Pmm
1400 SUBEND
Note
Do not specify a channel as part of the FETCh command, that
is, the syntax for the command in the compatability mode is
FETCh[: SCALar]:FOWer[: DC]?
Line No.
1300 Declares the subroutine. P$ is the string in which the reading is
returned to the calling program.
1310
Clears all the HP-IB buffers. (Pmm is the HP-IB address of the
instrument)
1320
Clears the Status Byte in the instrument.
1330 Sets up the instrument: Sets the wavelength for channel 2 to
ISOlnm; select MEASure mode; select channel 2; select dBm as
the units; set the trigger on; enable autoranging.
1340
Trigger the instrument.
1350, 1360
Performs a serial poll of the instrument, until bit 2 in the Status
Byte is set.
1365
This is the extra command required by the HP 8153A when in
HP 8152A compatability mode to read a value
Remote Operation H-3