Port Programming with arduino DUE

Official Hardware Mega Due
1

Hi, I need to read the output of an encoder that has 720 steps for one cycle of the B signal and 1 step every 360 deg. Using the digitalRead(PIN) function is not fast enough so I was wondering if it's possible to do readings directly from the pins like it is possible to do with Arduino UNO with the PIN function. I started to use Arduino DUE a few days ago, so I'm not so familiar with datasheets and where to look in order to find the port programming files.
Do you know something about this?
This is the coding I produces up to now, it works but it's too slow.

2

Time to research and watch YouTube:

Arduino "Due" direct port manipulation at DuckDuckGo

Lazy Link

3

Thanks for your help, I looked at the two links you attached, but I'm not sure if I'm doing the recalls properly, because there is not much on the Input.
For the Bwave I am using Pin number 3 which is on the Port C.28.
To read the value in input I used this but I think it's not the way I should use this command.

B_signal= PIOC ->PIO_PDSR= (1<<28);

Is there any chance you can explain to me how to assign to a variable the value which is either HIGH or LOW using port Programming?
Because having 720 pulses per revolution means that I need a really fast reading of the PIN state in order to be able to use the Encoder with a working speed of the engine of 4500rmp.

4

BLINK:
GitHub - bobc/bare-metal-sam3x: Bare bones projects for SAM3X (Arduino Due)

/* ========================================================================== */
/*                                                                            */
/*   main.c                                                                   */
/*   (c) 2017 Bob Cousins                                                     */
/*                                                                            */
/*   Description                                                              */
/*                                                                            */
/*   Minimal blink for SAM3X (Arduino Due)                                    */
/* ========================================================================== */

#include <stdint.h>

// LED on B27 (Arduino Due)
#define LED_PIN 27

// Output on B14 (Duet)
//#define LED_PIN 14

// PMC definitions
#define PMC_PCER0 *(volatile uint32_t *)0x400E0610

#define ID_PIOA 11
#define ID_PIOB 12
#define ID_PIOC 13
#define ID_PIOD 14
#define ID_PIOE 15
#define ID_PIOF 16

#define PMC_WPMR *(volatile uint32_t *)0x400E06E4

#define PMC_WPKEY 0x504D43

// PIO definitions

struct gpio {
  // + 0x00
  volatile uint32_t PIO_PER;
  volatile uint32_t PIO_PDR;
  volatile uint32_t PIO_PSR;
  volatile uint32_t res1;
  // + 0x10
  volatile uint32_t PIO_OER;
  volatile uint32_t PIO_ODR;
  volatile uint32_t PIO_OSR;
  volatile uint32_t res2;
  // + 0x20
  volatile uint32_t PIO_IFER;
  volatile uint32_t PIO_IFDR;
  volatile uint32_t PIO_IFSR;
  volatile uint32_t res3;
  // + 0x30
  volatile uint32_t PIO_SODR;
  volatile uint32_t PIO_CODR;
  volatile uint32_t PIO_ODSR;
  volatile uint32_t PIO_PDSR;
  // + 0x40
  volatile uint32_t PIO_IER;
  volatile uint32_t PIO_IDR;
  volatile uint32_t PIO_IMR;
  volatile uint32_t PIO_ISR;
  // + 0x50
  volatile uint32_t PIO_MDER;
  volatile uint32_t PIO_MDDR;
  volatile uint32_t PIO_MDSR;
  volatile uint32_t res4;
  // + 0x60
  volatile uint32_t PIO_PUDR;
  volatile uint32_t PIO_PUER;
  volatile uint32_t PIO_PUSR;
  volatile uint32_t res5;
  // + 0x70
  volatile uint32_t PIO_ABSR;
  volatile uint32_t res6[3];
  // + 0x80
  volatile uint32_t PIO_SCIFSR;
  volatile uint32_t PIO_DIFSR;
  volatile uint32_t PIO_IFDGSR;
  volatile uint32_t PIO_SCDR;
  // + 0x90
  volatile uint32_t res7[4];
  // + 0xA0
  volatile uint32_t PIO_OWER;
  volatile uint32_t PIO_OWDR;
  volatile uint32_t PIO_OWSR;
  volatile uint32_t res8;
  // ...
};

#define PIOA ((struct gpio *)0x400E0E00)
#define PIOB ((struct gpio *)0x400E1000)
#define PIOC ((struct gpio *)0x400E1200)
#define PIOD ((struct gpio *)0x400E1400)
#define PIOE ((struct gpio *)0x400E1600)
#define PIOF ((struct gpio *)0x400E1800)

#define PIOA_WPMR *(volatile uint32_t *)0x400E0EE4
#define PIOB_WPMR *(volatile uint32_t *)0x400E10E4
#define PIOC_WPMR *(volatile uint32_t *)0x400E12E4
#define PIOD_WPMR *(volatile uint32_t *)0x400E14E4
#define PIOE_WPMR *(volatile uint32_t *)0x400E16E4

#define PIO_WPKEY 0x50494F

void HardwareInit (void)
{
  // enable peripheral clock
	//  PMC_WPMR  = PMC_WPKEY << 8 | 0;
  PMC_PCER0 = 1 << ID_PIOB;

  // PIOC
	//  PIOC_WPMR  = PIO_WPKEY << 8 | 0;

  PIOB->PIO_PER = 1 << LED_PIN;
  PIOB->PIO_OER = 1 << LED_PIN;
  PIOB->PIO_OWER = 1 << LED_PIN;
}

void delay (volatile uint32_t time)
{
  while (time--)
    __asm ("nop");
}

void main()
{
  HardwareInit ();

  while (1)
  {
    PIOB->PIO_SODR = 1 << LED_PIN;
    delay (100000);
    PIOB->PIO_CODR = 1 << LED_PIN;
    delay (100000);
  }
}