Baseline project for platform Microchip PIC18F4550 (MPLAB X project with XC8 compiler)

Overview

This is a baseline project for the PIC18F4550 microcontroller with the following ready to use drivers:

• UART with dynamic configurable baudrate.
• ADC with static configurable number of channels.
• PWM (Pulse Width Modulation) with static configurable number of channels, using the highest possible frequency with the highest possible resolution (10 bits).
• DIO (Digital Input/Output) with static configurable number of channels.
• Master mode SPI (Serial Peripheral Interface) with static configurable clock frequency.
• Master mode IIC (Inter-Integrated Circuit) with static configurable clock frequency.
• Mcu (Micro-controller Unit) with static configurable clock signals to handle low-power modes (Sleep instruction for example).
• Timer 1 with external 32.768 Khz crystal for real-time applications.
• Flash with static configurable memory map to read/erase/write data or code on the code flash memory.

Most of the base drivers come with Sync and Async interfaces to set requests to the peripheral and letting the ISRs (interrupt service routines) handle the responses. These ISRs (per driver) come with a static configurable priority.

This project also comes with an example of bootloader over UART ( 🚧 work in progress) that shows the basic design and implementation of a bootloader software, control pass mechanism to application software, and modifying code flash routines.

Schematic

This is the schematic of the platform based on the pinguino 18f4550 platform, which has a LED connected to the RA4 pin and the RE3 pin connected to a reset button.

Code Examples

UART Hello world

/*
 * File:   main.c
 */
#include "inc/Board/UART/UART.h"

char msg[] = "Hello world!!\n";

void main(void) {
    Board_Init();
    UART_Init();
    UART_Open( 115200U );

    while(1){
        UART_TransmitAsync( 
            (const uart_byte*) msg,
            sizeof( msg ) );

        /* Do something else */
        __delay_ms( 500 );
    }
}

/*
 * File: board_config.c
 */
#include "../../inc/Board/board_config.h"
#include "../../inc/Board/UART/UART_internal.h"

void __interrupt(high_priority)
Board_HP_ISR(void){
}

void __interrupt(low_priority)
Board_LP_ISR(void){
    UART_ISR()
}

void Board_Init(){
    Mcu_Init();
    Mcu_Open();
}

SPI Hello world

/*
 * File:   main.c
 */
#include "inc/Board/SPI/SPI.h"

char spiBuffer[] = "Hello world!!\n";

void main(void) {
	SPI_Transaction_t spiTransaction = {
		.txBuffer = (SPI_byte_t*) spiBuffer,
		.rxBuffer = (SPI_byte_t*) spiBuffer,
		.txSize = sizeof(spiBuffer),
		.rxSize = sizeof(spiBuffer)
	};
    Board_Init();
    SPI_Init();
    SPI_Open();

    while(1){
        SPI_TransactionSync( &spiTransaction );

        /* Do something else */
        __delay_ms( 500 );
    }
}

/*
 * File: board_config.c
 */
#include "../../inc/Board/board_config.h"
#include "../../inc/Board/SPI/SPI_internal.h"

void __interrupt(high_priority)
Board_HP_ISR(void){
}

void __interrupt(low_priority)
Board_LP_ISR(void){
    SPI_ISR()
}

void Board_Init(){
    Mcu_Init();
    Mcu_Open();
}

IIC (I2C) Hello world

/*
 * File:   main.c
 */
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

#include "inc/Board/Dio/Dio.h"
#include "inc/Board/IIC/IIC.h"

#define ADXL345_SLAVE_ADDRESS           (0x53U << 1U)

#define ADXL345_REG_DEV_ID              (0x00U)
#define ADXL345_REG_POWER_CTL           (0x2DU)
#define ADXL345_REG_DATA_FORMAT         (0x31U)
#define ADXL345_REG_DATAX0              (0x32U)
#define ADXL345_REG_DATAX1              (0x33U)
#define ADXL345_REG_DATAY0              (0x34U)
#define ADXL345_REG_DATAY1              (0x35U)
#define ADXL345_REG_DATAZ0              (0x36U)
#define ADXL345_REG_DATAZ1              (0x37U)

#define ADXL345_REG_DATA_FORMAT_SET     (0x01U)
#define ADXL345_REG_POWER_CTL_SET       (0x08U)

#define DUMMY_BYTE                      (0xFFU);

#define BUFF_SIZE                       6U
IIC_byte_t buffer[BUFF_SIZE];

void main(void) {
    uint8_t  dev_id=0x00;
	IIC_Transaction_t iicTransaction = {
        .slave_address = (ADXL345_SLAVE_ADDRESS),
		.txBuffer = NULL,
		.txSize = 0U,
		.rxBuffer = NULL,
		.rxSize = 0U
	};

    Board_Init();

    Dio_Init();
    Dio_Open();

	IIC_Init();
	IIC_Open();

    Dio_WriteChannel( Dio_ch_0 , Dio_HIGH );

    /// Configure ADXL
    buffer[0] = ADXL345_REG_POWER_CTL;
    buffer[1] = ADXL345_REG_POWER_CTL_SET;/// +/- 4G range
    iicTransaction.txBuffer = buffer;
    iicTransaction.txSize = 2U;
    IIC_TransactionSync( &iicTransaction );

    buffer[0] = ADXL345_REG_DATA_FORMAT;
    buffer[1] = ADXL345_REG_DATA_FORMAT_SET;/// Medition mode
    iicTransaction.txBuffer = buffer;
    iicTransaction.txSize = 2U;
    IIC_TransactionSync( &iicTransaction );
    Dio_WriteChannel( Dio_ch_1 , Dio_HIGH );
    while(1){
        dev_id = 0x00;
                /// READ ID from ADXL345 (expected 0xE5U)
                buffer[0] = ADXL345_REG_DEV_ID;
                    iicTransaction.txBuffer = buffer;
                    iicTransaction.txSize = 1U;
                    iicTransaction.rxBuffer = buffer;
                    iicTransaction.rxSize = 1U;
                Dio_WriteChannel( Dio_ch_1 , Dio_LOW );//Signal Cancel Transaction Test
                IIC_TransactionAsync( &iicTransaction );
                __delay_us( 100 );
                IIC_CancelTransaction();
                Dio_WriteChannel( Dio_ch_1 , Dio_HIGH );
        /// READ ID from ADXL345 (expected 0xE5U)
        buffer[0] = ADXL345_REG_DEV_ID;
            iicTransaction.txBuffer = buffer;
            iicTransaction.txSize = 1U;
            iicTransaction.rxBuffer = buffer;
            iicTransaction.rxSize = 1U;
        IIC_TransactionAsync( &iicTransaction );
        while( IIC_ready != IIC_getStatus() ){ }

        dev_id = buffer[0];
        if( 0xE5U == dev_id ){
            LATAbits.LA4 = Dio_HIGH;
        }else{
            LATAbits.LA4 = Dio_LOW;
        }

        /// Read axis (from X0 buffer through Z1)
        buffer[0] = ADXL345_REG_DATAX0;
            iicTransaction.txBuffer = buffer;
            iicTransaction.txSize = 1U;
            iicTransaction.rxBuffer = buffer;
            iicTransaction.rxSize = BUFF_SIZE;
        IIC_TransactionAsync( &iicTransaction );
        while( IIC_ready != IIC_getStatus() ){ }
        __delay_ms( 500 );/// Debounce time
    }
}

ADC + PWM

/*
 * File:   main.c
 */
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

#include "Pwm.h"
#include "Adc.h"

void main(void) {
AdcCounts_t  counts;
    Board_Init();
    Adc_Init();
    Adc_Open();
    Pwm_Init();
    Pwm_Open();

    LATAbits.LA4 = 1U;

    while(1){
        Adc_ConvertSync( Adc_Ch_0 );
        counts = Adc_getCounts();

        Pwm_SetDutyCycle( Pwm_Ch_1,
            (Pwm_DutyCycle_t) counts );
        
        /* Do something else */
        __delay_ms( 500 );
        LATAbits.LA4 = !PORTAbits.RA4;
    }
}