Metrologic Optimus R, Руководство по программированию

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102 "C" Programming Guide For Optimus S/R
Relevant routines are grouped by different communication types and described separately
in the following sections.
clear_com
Purpose To clear the receive buffer.
Syntax
void clear_com (int port);
int port; /* COM port whose receive buffer is to be cleared */
Example clear_com (1); /* clear the receive buffer of COM 1 */
Description This routine clears all the data stored in the receive buffer. It can be used to
avoid mis-interpretation when overrun or other error occurs.
Return None
See Also com_overrun
close_com
Purpose To terminate communication and disable a specified COM port.
Syntax
int close_com (int port) ;
int port; /* COM port to be closed */
Example close_com (2); /* close COM 2 */
Description This routine disables the COM port specified.
Return
It always returns 1.
See Also open_com
com_eot
Purpose To check if there is any COM port transmission in progress.
Syntax int com_eot (int port) ;
int port; /* COM port to be checked */
Example while (!com_eot (1)); /* wait till prior transmission completed */
write_com (1,”NEXT STRING”);
Description This routine checks if there is any transmission still in progress. (eot = End Of
Transmission)
Return If transmission is completed, it returns 1.
Otherwise, it returns 0.