Specifications

SR400 with the GPIB Interface

PROGRAM EXAMPLE 3:

IBM PC, MICROSOFT BASIC, VIA GPIB

This program requires the Capital Equipment Corporation GPIB card for the IBM PC. It has firmware in

ROM to interface high level languages to the GPIB.

Subroutine calls in Microsoft BASIC are done to memory locations specified by the name of the subroutine.

The address is relative to the segment address specified by the DEF SEG statement preceding the CALL.

In this program, the CEC card's ROM starts at C000H, the system controller's address is 21, and the SR400 is

at GPIB address 23.

10 'EXAMPLE PROGRAM TO READ THE SR400 COUNTER DATA AND RAMP THE PORT1

20 'ANALOG OUTPUT USING IBM PC BASIC AND THE CAPITAL EQUIPMENT CORP.

30 'GPIB INTERFACE CARD

40 '

50 '

60 'SET THE COM MENU GPIB ADDR=23

70 '

80 DEF SEG = &HC000 'BASE ADDRESS OF CEC CARD

90 INIT=0: TRANSMIT=3: SEND=9: ENTER=21 'ADDRESSES OF CEC FIRMWARE ROUTINES

100 ADDR%=21: SYS%=0 'CONTROLLER ADDRESS

110 SR400%=23 'SR400 ADDRESS

120 '

130 'STRING DEFINITIONS

140 IN$="IFC UNT UNL REN MTA LISTEN 23 SDC" 'CLEAR SR400

150 CI$="CI0,0" 'COUNTER A INPUT=10 MHZ

160 CR$="CR;CS" 'RESET AND START NEW COUNT

170 QA$="QA1" 'READ COUNTER A DATA

180 P1$="PL1," 'SET PORT1 LEVEL

190 '

200 '

210 CALL INIT(ADDR%,SYS%) 'INIT CEC CARD

220 CALL TRANSMIT(IN$,STATUS%): GOSUB 480 'RESET SR400

230 FOR I=1 TO 500: NEXT I 'WAIT FOR RESET TO FINISH

240 '

250 X=0 'INIT PORT1 VALUE

260 '

270 CALL SEND(SR400%,CI$,STATUS%): GOSUB 480 'SET COUNTER A INPUT

280 '

290 'START NEXT COUNT PERIOD

300 CALL SEND(SR400%,CR$,STATUS%): GOSUB 480

310 '

320 CALL SEND(SR400%,QA$,STATUS%):GOSUB 480 'READ DATA

330 ANS$=SPACE$(20) 'CLEAR RESULT STRING

340 CALL ENTER(ANS$,LENGTH%,SR400%,STATUS%):GOSUB 480 'READ COUNTER DATA

350 N1=VAL(ANS$) 'INTO VARIABLE N1

360 IF N1<0 THEN GOTO 320 'IF COUNT PERIOD NOT DONE, TRY AGAIN

370 PRINT "COUNTER A = "; N1; 'ELSE PRINT VALUE

380 '