// ====================================================================================
// Archivo: main.c
// Dispositivo: PIC16F628A
// Funci n: Transmisor FM con QN8027, control por encoders, LCD I2C, EEPROM y RDS din mico
// ====================================================================================
#include <16F628A.h>
#device ADC=10
#use delay(clock=4000000)
#use i2c(master, sda=PIN_B0, scl=PIN_B1, slow)
// ===========================
// QN8027 (Transmisor FM)
// ===========================
#define QN8027_ADDRESS 0x58
void qn8027_write_reg(unsigned char reg, unsigned char value) {
i2c_start();
i2c_write(QN8027_ADDRESS);
i2c_write(reg);
i2c_write(value);
i2c_stop();
}
void qn8027_init(void) {
qn8027_write_reg(0x00, 0x01); // Reset
delay_ms(10);
qn8027_write_reg(0x01, 0x55); // Oscilador
qn8027_write_reg(0x06, 0x0F); // Potencia m xima
qn8027_write_reg(0x02, 0x00); // Standby
}
void qn8027_set_freq(unsigned int16 freq_val) {
unsigned char low = freq_val & 0xFF;
unsigned char high = freq_val >> 8;
qn8027_write_reg(0x04, low);
qn8027_write_reg(0x05, high);
}
void qn8027_start_tx(void) {
qn8027_write_reg(0x02, 0x88); // Modo transmisi n
}
void qn8027_set_power(unsigned char level) {
if(level > 15) level = 15;
qn8027_write_reg(0x06, level);
}
// ===========================
// EEPROM
// ===========================
#define ADDR_FREQ 0x00
#define ADDR_POT 0x02
unsigned char eeprom_read_byte(unsigned char addr) { return read_eeprom(addr); }
void eeprom_write_byte(unsigned char addr, unsigned char value) { write_eeprom(addr, value); }
// ===========================
// LCD I2C (PCF8574)
// ===========================
#define LCD_ADDR 0x4E
#define RS_COM 0
#define RS_DAT 1
#define LCD_EN 4
#define LCD_BL 8
void i2c_write_lcd(unsigned char value) {
i2c_start();
i2c_write(LCD_ADDR);
i2c_write(value);
i2c_stop();
}
void lcd_send_nibble(unsigned char nibble, unsigned char mode) {
unsigned char data = nibble | (mode ? RS_DAT : RS_COM) | LCD_BL;
i2c_write_lcd(data | LCD_EN);
delay_us(100);
i2c_write_lcd(data & ~LCD_EN);
}
void lcd_send_byte(unsigned char data, unsigned char mode) {
lcd_send_nibble(data & 0xF0, mode);
lcd_send_nibble((data << 4) & 0xF0, mode);
delay_ms(2);
}
void lcd_init(void) {
delay_ms(50);
lcd_send_nibble(0x30, RS_COM); delay_ms(5);
lcd_send_nibble(0x30, RS_COM); delay_us(150);
lcd_send_nibble(0x30, RS_COM); delay_us(150);
lcd_send_nibble(0x20, RS_COM); delay_us(150);
lcd_send_byte(0x28, RS_COM);
lcd_send_byte(0x08, RS_COM);
lcd_send_byte(0x01, RS_COM); delay_ms(2);
lcd_send_byte(0x06, RS_COM);
lcd_send_byte(0x0C, RS_COM);
}
void lcd_clear(void) { lcd_send_byte(0x01, RS_COM); delay_ms(2); }
void lcd_gotoxy(unsigned char x, unsigned char y) {
unsigned char address = (y == 1) ? 0x00 : 0x40;
address += (x - 1);
lcd_send_byte(0x80 | address, RS_COM);
}
void lcd_putc(char c) { lcd_send_byte(c, RS_DAT); }
void lcd_print(char *text) { while(*text) lcd_putc(*text++); }
// ===========================
// Encoders (Entrada)
// ===========================
#define ENC_FREQ_A PIN_A0
#define ENC_FREQ_B PIN_A1
#define ENC_FREQ_BTN PIN_A2
#define ENC_POT_A PIN_A3
#define ENC_POT_B PIN_A4
#define ENC_POT_BTN PIN_A5
unsigned char last_freq_a = 0;
unsigned char last_pot_a = 0;
signed char encoder_freq_read(void) {
signed char delta = 0;
unsigned char a = input(ENC_FREQ_A);
unsigned char b = input(ENC_FREQ_B);
if(a != last_freq_a) delta = (b != a) ? 1 : -1;
last_freq_a = a;
return delta;
}
signed char encoder_pot_read(void) {
signed char delta = 0;
unsigned char a = input(ENC_POT_A);
unsigned char b = input(ENC_POT_B);
if(a != last_pot_a) delta = (b != a) ? 1 : -1;
last_pot_a = a;
return delta;
}
unsigned char encoder_freq_pressed(void) { return !input(ENC_FREQ_BTN); }
unsigned char encoder_pot_pressed(void) { return !input(ENC_POT_BTN); }
// ===========================
// Variables globales
// ===========================
unsigned int16 frecuencia;
signed char potencia;
// ===========================
// Actualizar LCD
// ===========================
void actualizar_lcd() {
char buffer[16];
unsigned char mhz = frecuencia / 10;
unsigned char dec = frecuencia % 10;
unsigned char pot_pct = (unsigned char)potencia * 100 / 15;
lcd_clear();
sprintf(buffer, "Frec: %02u.%1uMHz", mhz, dec);
lcd_gotoxy(1,1); lcd_print(buffer);
sprintf(buffer, "Pot: %03u%%", pot_pct);
lcd_gotoxy(1,2); lcd_print(buffer);
}
// ===========================
// RDS Din mico (PS y RT)
// ===========================
char rds_ps[9] = "MiRadio ";
char rds_rt[65] = "Bienvenidos a la emisora FM QN8027!";
unsigned char rds_ps_index = 0;
unsigned char rds_rt_index = 0;
void qn8027_send_ps_block(void) {
unsigned char i = rds_ps_index * 2;
unsigned char b0 = rds_ps[i];
unsigned char b1 = rds_ps[i + 1];
qn8027_write_reg(0x0A + rds_ps_index, b0);
qn8027_write_reg(0x0A + rds_ps_index, b1);
rds_ps_index = (rds_ps_index + 1) % 4;
}
void qn8027_send_rt_block(void) {
unsigned char b0 = rds_rt[rds_rt_index];
unsigned char b1 = (rds_rt[rds_rt_index + 1] != '\0') ? rds_rt[rds_rt_index + 1] : ' ';
qn8027_write_reg(0x0E, b0);
qn8027_write_reg(0x0F, b1);
rds_rt_index += 2;
if (rds_rt_index >= 64 || rds_rt[rds_rt_index] == '\0') rds_rt_index = 0;
}
void qn8027_update_rds(void) {
qn8027_send_ps_block();
qn8027_send_rt_block();
}
// ===========================
// Programa principal
// ===========================
void main() {
// Configuraci n de puertos
set_tris_a(0xFF); set_tris_b(0x00); output_b(0x00);
lcd_init();
// Leer EEPROM
frecuencia = (unsigned int16)eeprom_read_byte(ADDR_FREQ) * 10;
frecuencia += eeprom_read_byte(ADDR_FREQ + 1);
potencia = eeprom_read_byte(ADDR_POT);
if(frecuencia == 0) frecuencia = 983;
if(potencia == 0) potencia = 15;
// Inicializar QN8027
qn8027_init();
qn8027_set_freq(frecuencia);
qn8027_set_power((unsigned char)potencia);
qn8027_start_tx();
actualizar_lcd();
while(TRUE) {
signed char d_freq = encoder_freq_read();
signed char d_pot = encoder_pot_read();
if(d_freq) {
frecuencia += d_freq;
if(frecuencia < 875) frecuencia = 875;
if(frecuencia > 1080) frecuencia = 1080;
qn8027_set_freq(frecuencia);
actualizar_lcd();
}
if(d_pot) {
potencia += d_pot;
if(potencia > 15) potencia = 15;
if(potencia < 0) potencia = 0;
qn8027_set_power((unsigned char)potencia);
actualizar_lcd();
}
if(encoder_freq_pressed()) {
eeprom_write_byte(ADDR_FREQ, frecuencia/10);
eeprom_write_byte(ADDR_FREQ+1, frecuencia%10);
}
if(encoder_pot_pressed()) {
eeprom_write_byte(ADDR_POT, (unsigned char)potencia);
}
// Actualizaci n din mica RDS
qn8027_update_rds();
delay_ms(50);
}
}
Descripción General del Archivo
Dos encoders rotativos (frecuencia y potencia)
Propiedades de Configuración del Microcontrolador
Módulo QN8027 (Transmisor FM)
Rango de frecuencia usado: 87.5 MHz a 108.0 MHz
EEPROM (Memoria No Volátil)
Módulo LCD I²C (Simplificado)
Estas son plantillas, pensadas para ser conectadas a una librería real.
Encoders Rotativos
Variables Globales
Funcionamiento del main()
Observaciones Importantes
Microcontrolador y Hardware
Transmisor FM (QN8027)
RDS (Radio Data System) dinámico
LCD I2C
EEPROM
Software / Loop principal
Uso de memoria y compilación
