RS-232 Operation Using QuickBASIC The following example shows how to send command instructio ns and
receive command responses over the RS-232 interface using QuickBASIC.
CLS
LOCATE 1, 1
DIM cmd$(100), resp$(1000)
’ Set up serial port for 9600 baud, even parity, 7 bits;
’ Ignore Request to Send and Carr ier Detect; Send line feed,
’ enable parity check, reserve 1000 bytes for input buffer
’
OPEN "com1:9600,e,7,2,r s,cd,lf,pe" FOR RANDOM AS #1 LEN = 1000
’
’ Put the multimeter into the remo te operation mode
PRINT #1, ":SYST:REM"
’
’ Query the multimeter’s id stri ng
’
PRINT #1, "*IDN?"
LINE INPUT #1, resp$
PRINT "*IDN? returned: ", resp$
’
’ Ask what revision of SCPI the mult imeter conforms to
PRINT #1, ":SYST:VERS?"
LINE INPUT #1, resp$
PRINT ":SYST:VERS? returned: ", resp$
’
’ Send a message to the multimeter’s display, and generate a beep
PRINT #1, ":SYST:BEEP;:DIS P:TEXT ’34401A’"
’
’ Configure the multimeter for dc voltage readings,
’ 10 V range, 0.1 V resolution, 4 read ings
PRINT #1, ":CONF:VOLT:DC 10, 0.1;:SAMP:COUN 4"
’ Trigger the readings, and fetc h the results
PRINT #1, ":READ?"
LINE INPUT #1, resp$
PRINT ":READ? returned: ", res p$
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