dc550_controller.c

一款经典的数字电话设计资料

/*****************************************************************************/
/*  CONFIDENTIAL                                                             */
/*  Sigpro Copyright 2003, All rights reserved                               */
/*****************************************************************************/
/*  CLIENT:  Telematrix                                                      */
/*  PROJECT: DC550 Digital Centrex Phone                                     */
/*  FILE:    dc550_controller.c                                              */
/*****************************************************************************/
/*  The Software Controller is responsible for interpreting and processing   */
/*  keypad commands and MDC switch commands properly and promptly            */
/*****************************************************************************/

#define __DC550_CONTROLLER_EXTERN__
#include "dc550_controller.h"
#include "dc550_interrupt.h"
#include "dc550_hookswitchmonitor.h"
#include "dc550_phonesm.h"

#include "dc550_usartdriver.h"


/******************************************************************************
 *  GLOBAL VARIABLES
 *****************************************************************************/
// Externally accessible global variables
unsigned int controller_keypress_keys[4];
unsigned int controller_keypress_states[4];
unsigned int controller_keypress_index;
unsigned int controller_modemreceive_commands[8];
unsigned int controller_modemreceive_index;

// Internally accessible global variables
unsigned int controller_hookswitch_updown;
unsigned int controller_periodiclastinterruptcounter;


/******************************************************************************
 *  FUNCTION: void controller_init(void)
 ******************************************************************************
 *  DESCRIPTION:
 *  This function is called during the initialization phase to initialize all
 *  of the software controller variables.
 *****************************************************************************/
void controller_init(void) {
  controller_keypress_index = 0;
  controller_hookswitch_updown = hookswitchmonitor_gethookswitchstate();
  controller_periodiclastinterruptcounter = interrupt_counter;
  phonesm_init();
}


/******************************************************************************
 *  FUNCTION: void controller_exec(void)
 ******************************************************************************
 *  DESCRIPTION:
 *  This function is called to execute the software controller task.  The
 *  function makes three inquiries:
 *  1) If a message was received through the modem, it calls
 *     phonesm_exec_modemcommand(.)
 *  2) If the hookswitch was toggles or keys were pressed or unpressed, it
 *     calls phonesm_exec_hookswitch(.) and/or phonesm_exec_keypress(.)
 *  3) If ten milliseconds have passed since the phonesm_exec_periodic(.)
 *     was last called, it calls phonesm_exec_periodic(.)
 *****************************************************************************/
void controller_exec(void) {
  // Declare counter and temporary variable
  unsigned int i;
  
  // Part 1: Check if a message was received through the modem
  for(i=0; i < controller_modemreceive_index; i++)
    phonesm_exec_modemcommand(controller_modemreceive_commands[i]);
  controller_modemreceive_index = 0;
  
  // Part 2A: Check if hookswitch changed states
  i = hookswitchmonitor_gethookswitchstate();
  if(controller_hookswitch_updown != i) {
    controller_hookswitch_updown = i;
    phonesm_exec_hookswitch(i);
  }
  
  // Part 2B: Check if any keys changed states
  for(i=0; i < controller_keypress_index; i++)
    phonesm_exec_keypress(controller_keypress_keys[i],
                          controller_keypress_states[i]);
  controller_keypress_index = 0;

  // Part 3: Check if it's time to call phonesm_exec_periodic(.)
  if((interrupt_counter - controller_periodiclastinterruptcounter) >=
     CONTROLLER_DURATION_PERIODIC) {
    phonesm_exec_periodic();
    controller_periodiclastinterruptcounter += CONTROLLER_DURATION_PERIODIC;
  }
}


/******************************************************************************
 *  FUNCTION:
 *  void controller_report_keypress(unsigned int key, unsigned int updown)
 ******************************************************************************
 *  DESCRIPTION:
 *  This function assumes that indicator is a valid index between 0 and
 *  39, and updown is either 1 or 0.
 *****************************************************************************/
void controller_report_keypress(unsigned int key, unsigned int updown) {
  controller_keypress_keys[controller_keypress_index] = key;
  controller_keypress_states[controller_keypress_index] = updown;
  controller_keypress_index++;
  // We may wish to check for overflow during the debugging process
}


/******************************************************************************
 *  FUNCTION: void controller_report_modemcommand(DC550MDCMessage command)
 ******************************************************************************
 *  DESCRIPTION:
 *  This function assumes that indicator is a valid index between 0 and
 *  39, and updown is either 1 or 0.
 *****************************************************************************/
void controller_report_modemcommand(DC550MDCMessage command) {

  controller_modemreceive_commands[controller_modemreceive_index] = command;
  controller_modemreceive_index++;
}


/******************************************************************************
 *  FUNCTION: unsigned int controller_gethookswitchstate(void)
 ******************************************************************************
 *  DESCRIPTION:
 *  This is an accessor function for the Phone State Machine's hookswitch
 *  state.
 *****************************************************************************/
unsigned int controller_gethookswitchstate(void) {
  return controller_hookswitch_updown;
}