/* * File: main.c * Author: boos * * Created on February 21, 2020, 7:49 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 = NOCLKDIV// CPU System Clock Selection Bit (NO CPU system divide) #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 = ENABLED // PLL Enable Bit (3x or 4x PLL Enabled) #pragma config STVREN = ON // Stack Overflow/Underflow Reset Enable (Stack Overflow or Underflow will 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 (Low-voltage programming disabled) #include // define your texts // (can be as many as you want, total length is around 6000 characters) char *myTexts[] = {"GREETINGS, NICE PEOPLE OF THE INTERNET! ", "HELLO THERE. GENERAL KENOBI, YOU ARE A BOLD ONE! ", "WHAT IS THE ANSWER TO THE ULTIMATE QUESTION OF LIFE, THE UNIVERSE, AND EVERYTHING? ", "42. ", "THANK YOU SO MUCH FOR WATCHING, AND I WILL SEE YOU NEXT TIME! "}; // how are your segments connected to the shift register? // map a b c d e f g . char map[] = {7, 8, 3, 2, 1, 6, 5, 4}; // declare functions void clearDisplay (int digits); unsigned char convertCharacterToPattern (char ASCII); void sendValue (unsigned char value); // define locations of shift register controls #define STROBE RC5 #define DATA RC4 #define CLOCK RC3 #define NEXT !RA5 // variables int text_index = 0, char_index = 0, adc_value, TIME_BUFFER, NEXT_BUFFER; // main function void main (void) { // set internal oscillator to 4MHz IRCF0 = 1; IRCF1 = 0; IRCF2 = 1; IRCF3 = 1; // weak pull-up for button TRISA5 = 1; WPUA5 = 1; nWPUEN = 0; // ADC settings // ADC sampling frequency per bit is F_osc/16 ADCS0 = 1; ADCS1 = 0; ADCS2 = 1; // result alignment ADFM = 0; // RC2 as analog input TRISC2 = 1; ANSC2 = 1; // select channel AN6 (which corresponds to RC2) CHS0 = 0; CHS1 = 1; CHS2 = 1; CHS3 = 0; CHS4 = 0; // turn the ADC on ADON = 1; // set outputs and disable analog features on pin RC3 TRISC5 = 0; TRISC4 = 0; TRISC3 = 0; ANSC3 = 0; // TIMER0 settings // internal clock, no prescaler, interrupt on overflow TMR0CS = 0; PSA = 1; TMR0IE = 1; // enable global interrupts GIE = 1; // begin of main program // clear all eight registers clearDisplay(8); // main loop while (1) { // get potentiometer position GO = 1; while (GO); adc_value = ADRESH; // has the "NEXT" button been pressed? if ((NEXT) && (NEXT_BUFFER == 0)) { // remove old text clearDisplay(8); // reset everything to display new text TIME_BUFFER = 0; char_index = 0; // advance to the next line of text, and go back // to the first one if we have arrived at the end text_index++; if (text_index >= sizeof(myTexts)/sizeof(myTexts[0])) { text_index = 0; } // reset debounce variable NEXT_BUFFER = 50; } } return; } // the interrupt service routine void __interrupt () isr (void) { // this is called abound 3900 times per second if (TMR0IF) { // increase the time buffer by 1 TIME_BUFFER++; // have we waited long enough for the text to // advance to the next letter? if (TIME_BUFFER > 4*adc_value + 100) { // reset the timing buffer variable TIME_BUFFER = 0; // pipe out the next text character to the shift registers sendValue(convertCharacterToPattern(myTexts[text_index][char_index])); STROBE = 1; STROBE = 0; // increase the character index, // and reset to 0 if we have reached the end char_index++; if (myTexts[text_index][char_index] == 0) { char_index = 0; } } // debounce the "NEXT" button if ((!NEXT) && (NEXT_BUFFER > 0)) { NEXT_BUFFER -= 1; } // reset interrupt flag TMR0IF = 0; } } // This function converts an ASCII character into its corresponding // 7-segment symbol. You can modify this function to create your own // custom 7-segment font. unsigned char convertCharacterToPattern (char ASCII) { // what is the character? switch (ASCII) { // numbers abcdefg. case '0': return 0b11111100; case '1': return 0b01100000; case '2': return 0b11011010; case '3': return 0b11110010; case '4': return 0b01100110; case '5': return 0b10110110; case '6': return 0b10111110; case '7': return 0b11100000; case '8': return 0b11111110; case '9': return 0b11110110; // letters abcdefg. case 'a': return 0b11101110; case 'A': return 0b11101110; case 'b': return 0b00111110; case 'B': return 0b00111110; case 'c': return 0b00011010; case 'C': return 0b10011100; case 'd': return 0b01111010; case 'D': return 0b01111010; case 'e': return 0b10011110; case 'E': return 0b10011110; case 'f': return 0b10001110; case 'F': return 0b10001110; case 'g': return 0b10111100; case 'G': return 0b10111100; case 'h': return 0b00101110; case 'H': return 0b01101110; case 'i': return 0b00100000; case 'I': return 0b01100000; case 'j': return 0b01111000; case 'J': return 0b11111000; case 'k': return 0b10101110; case 'K': return 0b10101110; case 'l': return 0b00111100; case 'L': return 0b00011100; case 'm': return 0b10101000; case 'M': return 0b10101000; case 'n': return 0b00101010; case 'N': return 0b11101100; case 'o': return 0b00111010; case 'O': return 0b11111100; case 'p': return 0b11001110; case 'P': return 0b11001110; case 'q': return 0b11100110; case 'Q': return 0b11100110; case 'r': return 0b00001010; case 'R': return 0b00001010; case 's': return 0b10110110; case 'S': return 0b10110110; case 't': return 0b00011110; case 'T': return 0b00011110; case 'u': return 0b00111000; case 'U': return 0b01111100; case 'v': return 0b00111000; case 'V': return 0b01111100; case 'w': return 0b01010100; case 'W': return 0b01010100; case 'x': return 0b01101110; case 'X': return 0b01101110; case 'y': return 0b01100110; case 'Y': return 0b01110110; case 'z': return 0b11011010; case 'Z': return 0b11011010; // symbols abcdefg. case '=': return 0b00010010; case '-': return 0b00000010; case '_': return 0b00010000; case 248: return 0b11000110; // degree sign case '\'': return 0b01000000; case '"': return 0b01000100; case '(': return 0b10011100; case '[': return 0b10011100; case '{': return 0b10011100; case ')': return 0b11110000; case ']': return 0b11110000; case '}': return 0b11110000; case '.': return 0b00000001; case ',': return 0b00100000; case ';': return 0b00100001; case '!': return 0b01000001; case '?': return 0b11001011; case ' ': return 0b00000000; // default symbol is an empty space default: return 0b00000000; } } // This function that an eight-bit value to // the CD4094 shift registers void sendValue (unsigned char value) { // auxiliary index variable int n = 0; // loop over all eight bits for (n = 0; n < 8; n++) { // Map the n-th bit to its corresponding // position in the shift register. This is // controlled by the array map[]. DATA = (value >> (map[n]-1)) & 1; // pulse the clock pin CLOCK = 1; CLOCK = 0; } } // This function clears the display by sending out zeros. void clearDisplay (int digits) { // send zeros DATA = 0; // send eight zeros for each digit for (int tmp=0; tmp<8*digits; tmp++) { CLOCK = 1; CLOCK = 0; } // update the registers STROBE = 1; STROBE = 0; }