// sleep_pwm.c
//
// timers during sleep
// pwm for LEDs

/*  Copyright (C) 2017 H.Poetzl
**	
**  This program is free software: you can redistribute it and/or
**  modify it under the terms of the GNU General Public License
**  as published by the Free Software Foundation, either version
**  2 of the License, or (at your option) any later version.
*/

// ------------------------------------------------
// configuration

#define NO_BIT_DEFINES
#include <pic16f18344.h>
#include <stdint.h>

#define CONFIG(k, n) __code static char __at _ ## k __ ## k = n

CONFIG(CONFIG1,  _FEXTOSC_OFF & _RSTOSC_HFINT1 & _CSWEN_ON & _CLKOUTEN_OFF);
CONFIG(CONFIG2,  _MCLRE_ON & _WDTE_OFF & _PPS1WAY_OFF);

#include "tear_leds.h"


void irq(void) __interrupt 0
{
    __asm
	BANKSEL PIR1
	BTFSC PIR1,TMR2IF
	BRA _tmr2

	BANKSEL PIR0
	BTFSC PIR0,TMR0IF
	BRA _tmr0

	RETFIE

    _tmr0:
	BCF PIR0,TMR0IF

	BANKSEL TMR0H
	MOVLW 0xF0
	MOVWF TMR0H
	CLRF TMR0L

	BANKSEL LEDCL
	BCF LEDCL,LEDC
	BSF LEDCL,LEDC
	RETFIE

    _tmr2:
	BCF PIR1,TMR2IF

	BANKSEL PR2
	INCF	PR2,F

	; BANKSEL T2CON
	; BCF T2CON,TMR2ON

	BANKSEL LEDBL
	BCF LEDBL,LEDB
	BSF LEDBL,LEDB
	RETFIE

    __endasm;
}

// --------------------------------------------------
// and our main entry point

void main()
{
    uint16_t data = 0;

    // all digital
    ANSELA = 0;
    ANSELB = 0;
    ANSELC = 0;

    // all input
    TRISA = 0xFF;
    TRISB = 0xFF;
    TRISC = 0xFF;

    // all one
    LATA = 0xFF;
    LATB = 0xFF;
    LATC = 0xFF;

    // all open drain
    ODCONA = 0xFF;
    ODCONB = 0xFF;
    ODCONC = 0xFF;

    __asm
	BANKSEL TRISA
	BCF LED0T,LED0
	BCF LED1T,LED1
	BCF LED2T,LED2
	BCF LED3T,LED3
	BCF LED4T,LED4
	BCF LED5T,LED5
	BCF LED6T,LED6
	BCF LED7T,LED7
	BCF LED8T,LED8
	BCF LED9T,LED9
	BCF LEDAT,LEDA
	BCF LEDBT,LEDB
	BCF LEDCT,LEDC
	BCF LEDDT,LEDD
	BCF LEDET,LEDE
	BCF LEDFT,LEDF
    __endasm;

    OSCCON3bits.CSWHOLD = 0;
    OSCCON1bits.NDIV = 1;

    /* configure Timer 0 */
    T0CON0 = 0;
    T0CON0bits.T0EN = 1;
    T0CON0bits.T016BIT = 1;
    T0CON0bits.T0OUTPS = 0b0000;	/* Postscaler = 1 */
    T0CON1 = 0;
    T0CON1bits.T0CS = 0b100;		/* Source = LFINTOSC */
    T0CON1bits.T0CS = 0b011;		/* Source = HFINTOSC */
    T0CON1bits.T0ASYNC = 1;
    T0CON1bits.T0CKPS = 0b0000;		/* Prescaler = 1 */

    TMR0H = 0x80;
    TMR0L = 0x00;

    /* configure Timer 2 */
    T2CON = 0;
    T2CONbits.TMR2ON = 0;		/* Timer is off */
    T2CONbits.T2CKPS = 0b00;		/* Prescaler = 1 */
    T2CONbits.T2OUTPS = 0b0000;		/* Postscaler = 1 */

    PR2 = 0xFF;
    TMR2 = 0;

    /* configure PWM */
    PWMTMRSbits.P5TSEL = 0b01;  /* Based on Timer2 */
    PWM5CON = 0;
    PWM5CONbits.PWM5EN = 1;     /* Enable PWM Module */
    PWM5CONbits.PWM5POL = 1;    /* Output Active Low */

    PWM5DCH = 0;
    PWM5DCL = 0;


    PMD0 = 0x43;	/* All but Peripherial Clock */
    PMD1 = 0xFA;	/* All but Timer 0,2 */
    PMD2 = 0x66;	/* All */
    PMD3 = 0xEF;	/* All but PWM 5 */
    PMD4 = 0x22;	/* All */
    PMD5 = 0x1F;	/* All */

    /* PPS */
    PPSLOCKbits.PPSLOCKED = 0;


    PIR0bits.TMR0IF = 0;		/* clear TMR0 irq */
    PIE0bits.TMR0IE = 1;		/* enable TMR0 irq */

    PIR1bits.TMR2IF = 0;		/* clear TMR2 irq */
    PIE1bits.TMR2IE = 1;		/* enable TMR2 irq */

    INTCONbits.PEIE = 1;		/* enable peripheral irq */
    INTCONbits.GIE = 1;			/* enable global irq */


    while (1) {
	__asm
	    SLEEP
	__endasm;	

	__asm
	    BANKSEL LATA	; during IRQ
	    BCF LED0L,LED0
	    BSF LED0L,LED0
	__endasm;

	data++;

	PWM5DCH = data >> 8;
	PWM5DCL = 0x40;			/* shortest pulse */

	TMR2 = 0xFE;			/* prime Timer 2 */
	PR2 = 0xFF;	

	LED6P = 0b00010;		/* put PWM on LED */
	T2CONbits.TMR2ON = 1;		/* start Timer 2 */
	// PWM5CONbits.PWM5EN = 1;     	/* enable PWM Module */

	while (PR2 == 0xFF);

	LED6P = 0b00000;		/* put GPIO on LED */
	// PWM5CONbits.PWM5EN = 0;     	/* disable PWM Module */
	T2CONbits.TMR2ON = 0;		/* stop Timer 2 */

#if 0

	__asm
	    BCF LED1L,LED1
	    BSF LED1L,LED1
	__endasm;
#endif
    }
}