/********************************************************************** * Copyright by Mekatronix 1998 * * Title motorme.c * * Programmer Keith L. Doty * * Date May 3, 1999 * * Version 1.1 * * Description * * This module controls the left and right wheel motors of the * * TALRIK robot. Functions perform motor initialization and motor * * speed control. Two PWM interrupt drivers for motor0 (PA5,OC3) * * (Right Wheel Motor) and motor1 (PA6, OC2) (Left Wheel Motor) * * control motor speed. * * * * Driver motor0 uses OC3 and motor1 uses OC2 timers for the PWM. * * * * Version History: * * * **********************************************************************/ /*************************** Includes *********************************/ #include #include /************************ End of Includes *****************************/ /*************************** Constants ********************************/ #define motor0 TOC3_isr #define motor1 TOC2_isr /*Full period for a motor in clock cycles. A clock cycle is 0.5 microseconds*/ #define PERIODM 65,500 /* One percent of motor period in clock cycles*/ #define PERIOD_1PC 655 #define LEFT_MOTOR 1 #define RIGHT_MOTOR 0 /************************ End of Constants ****************************/ /*************************** Prototypes *******************************/ #pragma interrupt_handler TOC2_isr, TOC3_isr; void init_motorme(void); void motor0(); void motor1(); void motorme(int, int); /************************ End of Prototypes ***************************/ /**************************** Globals *********************************/ /* Specifies the PWM duty cycle for motor0 and motor1 */ int duty_cycle[2]; /************************* End of Globals *****************************/ void init_motorme(void) /********************************************************************** * Function description: This routine enables the motor interrupt * * service routines and starts the PWM signal low. * * Returns: None * * * * Inputs * * Parameters: None * * Globals: None * * Registers: TCTL1,TMSK1, DDRD * * Outputs * * Parameters: None * * Globals: None * * Registers: TCTL1,TMSK1, * * Functions called: None * * Notes: This routine MUST be called to enable motor operation! * **********************************************************************/ { INTR_OFF(); /* Set OC2 and OC3 to output low */ SET_BIT(TCTL1,0xA0); CLEAR_BIT(TCTL1,0x50); SET_BIT(DDRD, 0x30); /* Set PWM duty cycle to 0 first */ duty_cycle[LEFT_MOTOR] = duty_cycle[RIGHT_MOTOR] =0; /* Enable motor interrupts on OC2 and OC3 */ SET_BIT(TMSK1,0x60); INTR_ON(); } /***********************End init_motorme ******************************/ void motorme(int index, int per_cent_duty_cycle) /************************************************************************ * Function description: * * Sets duty cycle and direction of motor specified by index. * * * * Returns: * * * * Inputs * * Parameters: index: 0 = left motor, 1 = right motor * * -100 <= per_cent_duty_cycle<= 100% * * Globals: None * * Registers: None * * Outputs * * Parameters: None * * Globals: duty_cycle[index] * 0 <= duty_cycle[index]<= PERIOD (Typically, PERIOD = 65,500) * * Registers: None * * Functions called: None * * Notes: Checks for proper input bounds. * ************************************************************************/ { if (per_cent_duty_cycle < 0) { per_cent_duty_cycle = -per_cent_duty_cycle; /* Make positive */ /* Set negative direction of motors */ if (index == RIGHT_MOTOR) CLEAR_BIT(PORTD,0x20); /*Right motor*/ if (index == LEFT_MOTOR) CLEAR_BIT(PORTD,0x10); /*Left motor*/ } else { /* Set positive direction of motors */ if (index == RIGHT_MOTOR) SET_BIT(PORTD, 0x20); /*Right motor*/ if (index == LEFT_MOTOR) SET_BIT(PORTD, 0x10); /*Left motor*/ } /* At this point per_cent_duty_cycle must be a positive number less * than 100. If not make it so. */ if (per_cent_duty_cycle > 100) per_cent_duty_cycle = 100; duty_cycle[index] = per_cent_duty_cycle*PERIOD_1PC; } /*********************** End motor ***********************************/ void motor0(void) /************************************************************************ * Function description: * * This interrupt routine controls the PWM to motor0 using OC3. For* * the TALRIK II robot motor0 is the left motor. * * Returns: None * * * * Inputs * * Parameters: None * * Globals: duty_cycle[RIGHT_MOTOR] * * Registers: TCTL1, TOC3 * * Outputs * * Parameters: None * * Globals: None * * Registers: TCTL1, TOC2, TFLG1 * * Functions called: CLEAR_BIT, SET_BIT * * Notes: init_motortk() assumed to have executed * ************************************************************************/ { /* Keep the motor off if no duty cycle specified.*/ // if(duty_cycle[RIGHT_MOTOR] == 0) // { // CLEAR_BIT(TCTL1, 0x10); // } // else // if(TCTL1 & 0x10) // { // TOC3 += duty_cycle[RIGHT_MOTOR]; /* Keep up for width */ // CLEAR_BIT(TCTL1,0x10); /* Set to turn off */ // } // else // { // TOC3 += (PERIODM - duty_cycle[RIGHT_MOTOR]); // SET_BIT(TCTL1,0x10); /* Set to raise signal */ // } CLEAR_FLAG(TFLG1,0x20); /* Clear OC3F interrupt Flag */ } /*********************** End motor0 ***********************************/ void motor1 (void) /************************************************************************ * Function description: * * This interrupt routine controls the PWM to motor1 using OC2. For * * the TALRIK II robot motor1 is the right motor. * * Returns: None * * * * Inputs * * Parameters: None * * Globals: duty_cycle[LEFT_MOTOR] * * Registers: TCTL1, TOC2 * * Outputs * * Parameters: None * * Globals: None * * Registers: TCTL1, TOC2, TFLG1 * * Functions called: CLEAR_BIT, SET_BIT * * Notes: init_motortk() assumed to have executed * ************************************************************************/ { /* Keep the motor off if no duty cycle specified.*/ // if(duty_cycle[LEFT_MOTOR] == 0) // { // CLEAR_BIT(TCTL1, 0x40); // } // else // if(TCTL1 & 0x40) // { // TOC2 += duty_cycle[LEFT_MOTOR]; /* Keep pulse width up for duty_cycle */ // CLEAR_BIT(TCTL1,0x40); /* Prepare to turn off next OC2 interrupt*/ // } // else // { // TOC2 += (PERIODM - duty_cycle[LEFT_MOTOR]); // SET_BIT(TCTL1,0x40); /* Prepare to raise signal next OC2 intr. */ // } CLEAR_FLAG(TFLG1,0x40); /* Clear OC2F interrupt Flag */ } /********************** End motor1 **************************************/