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giljr/unit_05_02_highLowPrioritiesInterruptions.c

Created November 30, 2019 18:37
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unit_05_02_highLowPrioritiesInterruptions.c
/* Project: Unit 05 - INT
Code: unit_05_02_highLowPrioritiesInterruptions.c
Objective: 2 interruptions & 1 pulling (High and low priorities setups):
By enable High Prior Interruption (TMR4), an LED (connected to PORTD.RD4)
will toggle every 200 ms, while, to comparative purpose,
by using polling technique, another LED (connected to PORTD.RD4)
will toggle every 1s, and again,
by enable Low Prior Interruption (TMR5), an LED (connected to PORTD.RD5)
will toggle every 1000 ms (1000ms/200ms => scaled 5:1)
The result, LEDs on RD4 and RD5, will consume interruptions, so its LEDs are
perfectly synchronized (well, not actually...), which is not the case with
the LED RD1 using pulling :/ that will depend on the main routine.
See Preview project too :D
See Calculation memory below:)
Author: microgenios, edited by J3
PIC Lessons: How to Start to Program PIC 18 - Step-by-step for Beginners!
Hardware: Development Boards (OPTIONS):
PicGenios: PIC18F4520 chip ( https://loja.microgenios.com.br/produto/kit-picgenios-pic18f4520-com-gravador-usb-microicd-licen-a-compilador-mikroc-pro-for-pic/23507 )
EasyPIC™ 7: PIC18F45K22 chip ( https://www.microchip.com/Developmenttools/ProductDetails/TMIK013 )
Software: Development Programmer/Debugger:
PICkit™ 2 ( http://ww1.microchip.com/downloads/en/DeviceDoc/PICkit%202%20v2.61.00%20Setup%20A.zip )
mikroProg suite for PIC ( https://www.mikroe.com/blog/mikroprog-suite-for-pic-version-2-3-1-released )
PDL: is a free-format English-like text that describes the flow of control and data in a
program. PDL is not a programming language. It is a collection of some keywords that enable
a programmer to describe the operation of a program in a stepwise and logical manner:
BEGIN
Call CONFIGMCU
Call CONFIGTMR0
Call CONFIGTMR1(*)
Call CONFIGGLABALINTERRUPTION
Call CONFIGINDIVIDUALVCTTMR0
Call CONFIGINDIVIDUALVCTTMR1(*)
DO FOREVER (ISR1)
IF Timer0 overflow THEN
Toggle PORTD reg. bit 0 on/off
Recharge Registers TMR0L/TMR0R
Clear TMR0's overflow flag
ENDIF
ENDDO (ISR1)
DO FOREVER (ISR2)
IF Timer1 overflow THEN
IF (Counter > 4) THEN
Toggle PORTD reg. bit 0 on/off
ENDIF
Recharge Registers TMR0L/TMR0R
Clear TMR0's overflow flag
ENDIF
ENDDO (ISR2)
BEGIN/CONFIGMCU
Pre-compilation Directives (config PORTD as digital)
Configure options for PIC18F45K22 & PIC18F4520
Configure all PORTD as digital output (init all LEDs off)
END/CONFIGMCU
BEGIN/CONFIGTMR0
Config T0CON (200ms)
Charge TMR0L & TMR0H's acumulator initial value
Clear overflow's flag
Turn TMR0 on
END/CONFIGTMR0
BEGIN/CONFIGTMR1
Config T1CON (250ms x 4)
Charge TMR0L & TMR0H's acumulator initial value
Clear overflow's flag
Turn TMR1 on
END/CONFIGTMR1
BEGIN/CONFIGGLABALINTERRUPTION
Config general interruptions High & Low (GIEH & GIEL)
Config interruption priority (IPEN)
END/CONFIGGLABALINTERRUPTION
BEGIN/CONFIGINDIVIDUALVCTTMR0
Config IF, IP & IE vectors (Flag, Prior & Enable)
END/CONFIGINDIVIDUALVCTTMR0
BEGIN/CONFIGINDIVIDUALVCTTMR1
Config IF, IP & IE vectors (Flag, Prior & Enable)
END/CONFIGINDIVIDUALVCTTMR1
END
Date: Nov 2019
*/
/* ---------------------Calculation Memory ------------------------------------
Interrupton: which registers must be set up(Timer0)? T0CON, TMROH & TMR0L
Hardware: picGenios and easyPIC v7 boards
Machine Cycle = FOSC/4 -> 8MHz/4 -> 2MHz -> p = 0.5us
**************************
Formulae: 200ms (TMR0)
OverflowTime = P_MacCycle * Prescale * (Mode_16bits - InitialCounter)
200000us = 0.5us * 32 * (65536 - X)
200000 / (0.5 * 32) = 65536 - X
12500 = 65536 - X
12500 - 65536 = - X (-1)
53036 = X
X = 53036 (InitialCounter - inside two registers TMR0L e TMR0H)
Transform the number in HEX: CF 2C
****************
T0CON = 0B00000100 (see datasheet)
TMR0L = OX CF;
TMR0H = 0X 2C;
****************
Formulae: 1000ms (TMR1), max is ~262 ms, so get 250 x 4 = 1000ms
OverflowTime = P_MacCycle * Prescale * (Mode_16bits - InitialCounter)
250000us = 0.5us * 8 * (65536 - X)
250000 / (0.5 * 8) = 65536 - X
62500 = 65536 - X
62500 - 65536 = - X (-1)
3036 = X
X = 3036 (InitialCounter - inside two registers TMR0L e TMR0H)
Transform the number in HEX: 0B DC
****************
T1CON = 0B00110010 (see datasheet)
TMR1H = 0X 0B;
TMR1L = 0X DC;
****************
Good Practices: Before turn on any peripherals, please configure it first;);
in other words, in configuration mode init TM0 as late as possible;)
-------------------------------------------------------------------------
Date: nov 2019
*/
#define TRUE 1
// Prototypes:
void configMCU(); // Set PORT & TRIS
void configTMR0(); // Set TMR0's mode, ps, etc
void configTMR1(); // Set TMR1's mode, ps, etc
void configGlobalInterruption(); // Set GIEH & GIEL & IPEN
void configIndividualVctTMR0(); // Set individual TMR0 interruptions vectors (IF, IP & IE)
void configIndividualVctTMR1(); // Set individual TMR1 interruptions vectors (IF, IP & IE)
// Goto Menu TOOLS > Interrupt Assistance
void INTERRUPTION_HIGH() iv 0x0008 ics ICS_AUTO
{ // 0X008h is high priority
// whereas 0x018h is low
if(INTCON.TMR0IF == 1)
{
PORTD.RD0 = ~LATD.RD0; // Toggle LED bit 0
// Never ever forget this block!
// or your program loop and is a goner o/
TMR0H = 0XCF; // Recharge acumulator
TMR0L = 0X2C;
INTCON.TMR0IF = 0; // Clear flag & reset interruption cycle
}
}
void INTERRUPTION_LOW() iv 0x0018 ics ICS_AUTO {
volatile unsigned char counter;
if(PIR1.TMR1IF == 1)
{
counter++; // By using counter you can make this
// time as big as you wish:)
if(counter == 4) // Overflow at 250ms x 4 = 1000ms
{
PORTD.RD4 ^= 1; // Toggle LED bit 2
counter = 0;
}
TMR1H = 0X0B; // Recharge acumulator
TMR1L = 0XDC;
PIR1.TMR1IF = 0; // Clear Flag
}
}
void configMCU() // Timer0 Port & Directions
{
#ifdef P18F45K22
ANSELD = 0;
#else
ADCON1 |= 0X0F; // Analog pinouts
#endif
TRISD = 0;
PORTD = 0; // LEDs' control pins
}
void configTMR0() // TIMER0 em 200ms
{
#ifdef P18F45K22
T0CON = 0B00000100; // Timer OFF, Mod 16-bits, Mode Timer, Prescale 1:32
#else
T0CON = 0B00000100; // Timer OFF, Mod 16-bits, Mode Timer, Prescale 1:32
#endif
TMR0H = 0XCF;
TMR0L = 0X2C;
INTCON.TMR0IF = 0; // Clear Flag
T0CON.TMR0ON = 1; // Timer0 on!
}
void configTMR1() // TIMER1 em 1000ms
{
#ifdef P18F45K22
T1CON = 0B00110010; // Timer1 OFF, Mod 16-bits, Mode Timer, Prescale 1:8
#else
T1CON = 0B10110000; // Timer1 OFF, Mod 16-bits, Mode Timer, Prescale 1:8
#endif
TMR1H = 0X0B;
TMR1L = 0XDC;
PIR1.TMR1IF = 0; // Clear Flag
T1CON.TMR1ON = 1; // Timer1 on!
}
void configGlobalInterruption() // Interruptions's master keys
{
INTCON.GIEH = 1; // High priority enabled
INTCON.GIEL = 1; // Low prioritY enabled
RCON.IPEN = 1; // Compatibility family 16F (just one level)
// If = 1 two priorities levels (PIC18F)
// If = 0, GIEL not applicable!
}
void configIndividualVctTMR0()
{
// See datasheet page 133
INTCON.TMR0IF = 0; // Overflow flag; please init zero
INTCON2.TMR0IP = 1; // Interruption priority vector: HIGH
INTCON.TMR0IE = 1; // TIMER0's interruption enabled
}
void configIndividualVctTMR1()
{
// See datasheet page 133
PIR1.TMR1IF = 0; // Overflow flag; please init zero
IPR1.TMR1IP = 0; // Interruption priority vector: LOW
PIE1.TMR1IE = 1; // TIMER0's interruption enabled
}
void main() {
configMCU(); // configure CHIP
configTMR0(); // configure TMR0 master ints keys
configTMR1(); // configure TMR1 master ints keys
configGlobalInterruption(); // Configure globals ints
configIndividualVctTMR0(); // configure TMR0 indiviadual vectors for each time
configIndividualVctTMR1(); // configure TMR1 indiviadual vectors for each time
//while(TRUE); // Free Program
while(TRUE)
{
PORTD.RD5 = ~LATD.RD5;
Delay_ms(1000); // Killing processor here!
// In 1000ms, 5 interruptions potentially
}
}
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