/* * File: main.c * Author: boos * * Created on February 26, 2022, 3:42 PM */ // CONFIG1 #pragma config FOSC = INTOSC // Oscillator Selection Bits (INTOSC oscillator: I/O function on CLKIN pin) #pragma config WDTE = OFF // Watchdog Timer Enable (WDT disabled) #pragma config PWRTE = OFF // Power-up Timer Enable (PWRT disabled) #pragma config MCLRE = OFF // MCLR Pin Function Select (MCLR/VPP pin function is digital input) #pragma config CP = OFF // Flash Program Memory Code Protection (Program memory code protection is disabled) #pragma config BOREN = OFF // Brown-out Reset Enable (Brown-out Reset disabled) #pragma config CLKOUTEN = OFF // Clock Out Enable (CLKOUT function is disabled. I/O or oscillator function on the CLKOUT pin) #pragma config IESO = OFF // Internal/External Switchover Mode (Internal/External Switchover Mode is disabled) #pragma config FCMEN = OFF // Fail-Safe Clock Monitor Enable (Fail-Safe Clock Monitor is disabled) // CONFIG2 #pragma config WRT = OFF // Flash Memory Self-Write Protection (Write protection off) #pragma config CPUDIV = CLKDIV6 // CPU System Clock Selection Bit (CPU system clock divided by 6) #pragma config USBLSCLK = 48MHz // USB Low SPeed Clock Selection bit (System clock expects 48 MHz, FS/LS USB CLKENs divide-by is set to 8.) #pragma config PLLMULT = 3x // PLL Multipler Selection Bit (3x Output Frequency Selected) #pragma config PLLEN = DISABLED // PLL Enable Bit (3x or 4x PLL Disabled) #pragma config STVREN = OFF // Stack Overflow/Underflow Reset Enable (Stack Overflow or Underflow will not cause a Reset) #pragma config BORV = LO // Brown-out Reset Voltage Selection (Brown-out Reset Voltage (Vbor), low trip point selected.) #pragma config LPBOR = OFF // Low-Power Brown Out Reset (Low-Power BOR is disabled) #pragma config LVP = OFF // Low-Voltage Programming Enable (High-voltage on MCLR/VPP must be used for programming) #include // define useful abbreviations #define LED1 RC4 #define LED2 RC3 #define LED3 RC2 #define LED4 RC0 #define SW_ON RC1 #define SW_UP RA1 #define SW_DN RA0 // time variables int t = 0; int seconds = 0; int minutes = 0; // debouncing variables int SW_ON_buffer = 0; int SW_UP_buffer = 0; int SW_DN_buffer = 0; // status variable int STATUS_ON = 1; // main function void main (void) { // configure IO pins TRISC0 = 0; ANSC0 = 0; TRISC2 = 0; ANSC2 = 0; TRISC3 = 0; ANSC3 = 0; TRISC4 = 0; TRISC1 = 1; ANSC1 = 0; TRISC5 = 0; // set the internal oscillator frequency to 4MHz IRCF3 = 1; IRCF2 = 1; IRCF1 = 0; IRCF0 = 1; // enable the external interrupt INTE = 1; // configure TIMER1 TMR1CS1 = 1; TMR1CS0 = 0; T1OSCEN = 1; // use the external clock TMR1GE = 0; // disable the gating nT1SYNC = 1; // allow TIMER1 to run in SLEEP mode TMR1IE = 1; // enable interrupt on overflow TMR1ON = 1; // turn TIMER1 on // turn on peripheral and global interrupts PEIE = 1; GIE = 1; // configure TIMER2 to ~4kHz PWM mode T2CKPS0 = 0; T2CKPS1 = 0; // set TIMER2 prescaler to 1:1 PR2 = 255; // set period register (to which TIMER2 value is compared) TMR2ON = 1; // turn TIMER2 on // configure PWM1 module PWM1DCH = 0; // most significant 8 bits of the duty/cycle value, 0..255 PWM1DCL = 0; // least significant 2 bits of the duty/cycle value, 0 or 1 PWM1EN = 1; PWM1OE = 1; // turn PWM module on // main loop while (1) { // is the UP button pressed? // (to debounce the signal, react only if it hasn't been pressed in a while) if (SW_UP && (SW_UP_buffer == 0)) { // increase the minutes all the way up to 12pm if (minutes < 1440) { minutes++; } // refill the debounce buffer variable SW_UP_buffer = 10; } // is the DOWN button pressed? // (to debounce the signal, react only if it hasn't been pressed in a while) if (SW_DN && (SW_DN_buffer == 0)) { // increase the minutes all the way down to 12pm if (minutes > 0) { minutes--; } // refill the debounce buffer variable SW_DN_buffer = 10; } // debounce buttons if (SW_UP_buffer > 0) { SW_UP_buffer--; } if (SW_DN_buffer > 0) { SW_DN_buffer--; } if (SW_ON_buffer > 0) { SW_ON_buffer--; } // go to sleep? if (STATUS_ON == 0) { // turn all LEDs off LED1 = 0; LED2 = 0; LED3 = 0; LED4 = 0; // disable PWM module PWM1DCH = 0; PWM1DCL = 0; PWM1EN = 0; // reset the pushbutton debounce variable SW_ON_buffer = 0; // and finally, go to sleep SLEEP (); // waking up? } else { // turn PWM module back on PWM1EN = 1; // adjust panel voltage if (minutes <= 720) { PWM1DCH = (unsigned char) (minutes / 3); } else { PWM1DCH = (unsigned char) ((minutes - 720) / 3); } // LED animation t = (TMR1H - 128) / 42; if (t == 0) { LED1 = 1; LED2 = 0; LED3 = 0; } else if (t == 1) { LED1 = 0; LED2 = 1; LED3 = 0; } else { LED1 = 0; LED2 = 0; LED3 = 1; } // is it AM? if (minutes <= 720) { LED4 = 0; } else { LED4 = 1; } } } return; } // interrupt service routine void __interrupt () isr (void) { // ON/OFF button has been pressed if (INTF) { // only react if it has just been pressed if (SW_ON_buffer == 0) { // toggle the clock's status from ON to OFF, or vice versa STATUS_ON = 1 - STATUS_ON; // debounce the pushbutton SW_ON_buffer = 500; } // clear external interrupt flag INTF = 0; } // TIMER1 overflow (occurs once per second) if (TMR1IF) { // update the time seconds++; if (seconds >= 60) { seconds = 0; minutes++; if (minutes >= 1440) { minutes = 0; } } // reset timer back to 127, so that an overflow occurs in another second TMR1H = 127; TMR1L = 0; // clear TIMER1 interrupt flag TMR1IF = 0; } }