Listing 7 (assert.c)

/***    MODEM CONTROL AND STATUS ROUTINES    ***/

#include "serial.h"

extern int portbase;

/***      USE TO SET CONTROL BITS IN MCR     ***/

void Assert(int request)
{
  int Current_Value;
  
  Current_Value = inp(portbase + MCR);
  
  outp(portbase + MCR,(Current_Value | request));
}

/***   USE TO TURN OFF CONTROL BITS IN MCR   ***/

void Assert_Off(int request)
{
  int Current_Value;
  
  Current_Value = inp(portbase + MCR);
  
  outp(portbase + MCR,(Current_Value & (OxFF - request)));
}

/***    GIVES STATUS OF CONTROL BIT IN MSR   ***/

int Status(int request)
{
  int Current_Value;
  
  Current_Value = (inp(portbase + MSR) & request);
  
  return(Current_Value);
}
/* End of File */