Specifications

SR400 with the RS-232 Interface
50
PROGRAM EXAMPLE 1:
IBM PC, BASIC, VIA RS-232
In this example, the IBM PC's serial port (known as COM1:) is used to communicate with the SR400. Only
two wires between the IBM PC's COM1: port and the SR400 are needed (pins #2 & #3 of the 25 pin RS-232
connector), but pins 5,6,8, and 20 should be connected together on the connector at the IBM end.
10 'EXAMPLE PROGRAM TO READ THE SR400 COUNTER DATA AND RAMP THE PORT 1
20 'ANALOG OUTPUT USING IBM BASIC AND THE COM1: RS-232 PORT.
30 '
40 '
50 'SET THE COM MENU OF THE SR400 FOR RS-232 BAUD=9600
60 ' RS-232 BITS=8
70 ' RS-232 PARITY=NONE
80 ' RS-232 WAIT=6
90 ' RS-232 ECHO=OFF
100 '
110 '
120 OPEN "COM1:9600,N,8,2,CS,DS,CD" AS #1
130 '
140 'SETUP COM1: PORT TO 9600 BAUD, NO PARITY, 8 DATA BITS, 2 STOP BITS,
150 'IGNORE CTS (CLEAR TO SEND), DSR (DATA SET READY),
160 'AND CD (CARRIER DETECT).
170 '
180 PRINT #1," " 'CLEAR COM1: BY SENDING SPACES
190 PRINT #1,"RC0" 'RESET SR400
200 FOR I=1 TO 500: NEXT I 'WAIT FOR RESET TO FINISH
210 X=0 'INIT PORT1 VALUE TO ZERO
220 PRINT #1,"CI0,0" 'SET COUNTER A INPUT TO 10 MHZ
230 '
240 '
250 PRINT #1,"CR;CS" 'RESET COUNTER;START NEW COUNT PERIOD
260 '
270 PRINT #1,"QA1" 'READ COUNTER A VALUE
280 INPUT #1,N1 'INTO VARIABLE N1
290 IF N1=-1 THEN GOTO 270 'IF COUNT PERIOD NOT DONE, LOOP AND TRY
AGAIN
300 PRINT "COUNTER A = "; N1; 'ELSE IF COUNT FINISHED, PRINT RESULT
310 '
320 X = X + .005 'INCREMENT PORT1 OUTPUT BY 5 MV
330 IF X>10 THEN X=0 'RESET RAMP IF AT 10 VOLTS
340 PRINT #1,USING "PL1,##.###"; X 'SET PORT1 OUTPUT VOLTAGE
350 PRINT "PORT1 = "; X 'PRINT PORT1 VALUE
360 '
370 GOTO 250 'LOOP FOREVER