Rockwell Automation 1771-DB BASIC MODULE - Manual (Page 291)

Chapter
Call Routines 69–127 13
13 -33
Use CALL 96 to clear port PRT1 receive and transmit buffers.
Input and Output Arguments
This routine has one input and no output argument. The input argument is
the buffer you want to clear:
0 to clear the transmit buffer
1 to clear the receive buffer
2 to clear both buffers
Syntax
PUSH buffer selection
CALL 96
Example
>1 REM EXAMPLE PROGRAM
>10 PUSH 0 : CALL 96 : REM CLEAR PRT1 TRANSMIT BUFFER
>30 END
Use CALL 97 to enable the Data Terminal Ready (DTR) signal from port
PRT2. The DTR signal is enabled by default when you power up the
BASIC module. This call re-enables the DTR if it has been disabled by
CALL 98.
Input and Output Arguments
This routine has no input and no output arguments.
Syntax
CALL 97
Example
>1 REM EXAMPLE PROGRAM
>10 CALL 97 : REM ENABLE DTR SIGNAL
>30 END
CALL 96: Clear PRT1
Receive/Transmit Buffers
CALL 97: Enable Port PRT2
DTR Signal