'*************************************************************************

'**                             DMM197.BAS                              **

'**     This program retrieves values from the Keithlty 197 DMM.        **

'*************************************************************************



ON ERROR GOTO errtrap



'*************************************************************************

'**     Open the COM port 1 and power up the 500-SERIAL. Wait for it to **

'**     reset. Set Baud rate for 19200, no parity, 8 bits, and 2 stop   **

'**     bits.                                                           **

'*************************************************************************



        OPEN "COM1:19200,N,8,2,CS,DS,CD" FOR RANDOM AS #1

        FOR I = 1 TO 1000: NEXT I               'Slight delay



'*************************************************************************

'**     Send five carriage returns separated by a short delay to allow  **

'**     the 500-SERIAL to set it's baud rate.                           **

'*************************************************************************



        FOR I = 1 TO 5

                PRINT #1, CHR$(13); : FOR T = 1 TO 500: NEXT T

        NEXT I



'*************************************************************************

'**     Turn echo off to avoid reading echoed characters as readings.   **

'*************************************************************************



        PRINT #1, "EC;0"                     'EC = Echo, 0=off, 1=on

        FOR I = 1 TO 1000: NEXT I            'Wait for the receive

                                             'buffer for COM port to fill

      

        A$ = INPUT$(LOC(1), #1)              'Now empty the input buffer

                                             'of garbage and echoed

                                             'characters.



'*************************************************************************

'**     Send initialization commands to the 500-SERIAL and 556          **

'*************************************************************************



        CLS

        PRINT #1, "I":                       'Send 'Init' command.

        PRINT #1, "RE;20"                    'Send Remote Enable.

        PRINT #1, "OA;20;R0G0X"              'Send Auto Range, Readings

                                             'with prefix data format.

        PRINT #1, "OA;20;U0X"                'Get 197 Status word.

        PRINT #1, "EN;20"                    'Put 197 into talker mode.

        INPUT #1, STATUS$                    'Place status in STATUS$

        LOCATE 1, 1: PRINT STATUS$           'Print Status$

                                

        WHILE INKEY$ = ""

                PRINT #1, "OA;20;T4X"        'Continous on X

                PRINT #1, "EN;20"            'Retrieve a data point, place

                INPUT #1, volts$             'data in variable 'volts$'.

                PRINT volts$                 'Print data

        WEND

        PRINT #1, "L;20"                     'Put 197 back into Local Mode.

        CLOSE #1                             'Close COM port.

        END



errtrap: RESUME NEXT