SPI clash . OLED and NFC

Projects Programming
1

I have an NFC/RFID module connected to ICSP pins and an OLED connected to the SPI I/O pins as in the sketch below.

The oled runs fine on its own and the RFID runs fine on its own. When both are called the RFID works but not the OLED.

In the sketch the startup OLED routine works then once the RFID is called it wont then display again.

I think its how the SPI is setup but I thought I had this working......I havent included the readRfid(); as i think the issue is in the SPI setup.

#include <SPI.h>
#include <PN532_SPI.h>

#include "PN532.h"
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1351.h>


int powerpinRead;

#define sclk 52
#define mosi 51
#define dc   A2
#define cs   53
#define rst  4

#define BLACK           0x0000
#define BLUE            0x001F
#define RED             0xF800
#define GREEN           0x07E0
#define CYAN            0x07FF
#define MAGENTA         0xF81F
#define YELLOW          0xFFE0  
#define WHITE           0xFFFF

PN532_SPI pn532spi(SPI, 10);
PN532 nfc(pn532spi);
Adafruit_SSD1351 tft = Adafruit_SSD1351(cs, dc, rst); 

boolean success;
String cardNum;
//unsigned long RFID;

uint8_t secs = 0;


void setup(void) {
  Serial.begin(9600);

  
  tft.begin();
    tft.fillRect(0, 0, 128, 128, BLACK);
  tft.setCursor(30, 5);
  tft.setTextColor(WHITE);
  tft.setTextSize(2);
  tft.println("Suzuki");
  tft.setTextSize(4);
  tft.println(" 121");
  delay (2000);
 
  

  
  
  uint16_t time = millis();
 // tft.fillRect(0, 0, 128, 128, BLACK);
  time = millis() - time;

nfc.begin();
uint32_t versiondata = nfc.getFirmwareVersion();
  if (! versiondata) {
  Serial.print("Didn't find PN53x board");
  while (1); // halt
  }
  nfc.setPassiveActivationRetries(0x01);
  nfc.SAMConfig();
 
  
  
}
void loop() 
{
Serial.println("loop running");

readRfid();
powerpinRead = (success);
 

}
2

I have everything working now until I call the RTCnow sub-routine. Then instead of displaying the RTC (by registering a HIGH from the NFC sub) the display goes blank .

Even if i commrnt out the RFID and just put the RTC in the loop it stops displaying. I know the OLED and RTC work together on another program but some how when this loop calls the same RTC code it crashes.

#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1351.h>
#include <PN532_SPI.h>
#include "PN532.h"
#include "RTClib.h"
PN532_SPI pn532spi(SPI, 10);
PN532 nfc(pn532spi);
RTC_DS3231 rtc;

#define dc   A2 
#define cs   53
#define rst  4

#define BLACK           0x0000
#define BLUE            0x001F
#define RED             0xF800
#define GREEN           0x07E0
#define CYAN            0x07FF
#define MAGENTA         0xF81F
#define YELLOW          0xFFE0  
#define WHITE           0xFFFF

Adafruit_SSD1351 tft = Adafruit_SSD1351(cs, dc, rst);
boolean success;
String cardNum;
//unsigned long RFID;
int powerPin = 13;//was 3
int powerpinRead;
int prevpowerpinRead = LOW;
int powerpinState = LOW;
long time = 0;         
long debounce = 200;   
float p = 3.1415926;
char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
uint8_t secs = 0;

void setup(void) {
 Serial.begin(9600);
 
 
  tft.begin();
  tft.fillRect(0, 0, 128, 128, BLACK);
  tft.setCursor(30, 5);
  tft.setTextColor(WHITE);
  tft.setTextSize(2);
  tft.println("Suzuki");
  tft.setTextSize(4);
  tft.println(" 112");
  delay (2000);
 //  tft.fillRect(0, 0, 128, 128, BLACK);
 
 nfc.begin();
uint32_t versiondata = nfc.getFirmwareVersion();
  if (! versiondata) {
  Serial.print("Didn't find PN53x board");
  while (1); // halt
  }
  nfc.setPassiveActivationRetries(0x01);
  nfc.SAMConfig();
   
  pinMode(powerPin, OUTPUT); 

 uint16_t time = millis();
 // tft.fillRect(0, 0, 128, 128, BLACK);
  time = millis() - time;
 
 
 }
void loop() 
{
 readRfid();
 powerpinRead = (success);
}

void readRfid()
{
  
  uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 };  // Buffer to store the returned UID
  uint8_t uidLength;                        // Length of the UID (4 or 7 bytes depending on ISO14443A card type)
  success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, &uid[0], &uidLength);
  if (success) {
    //Serial.println(success);
    Serial.println("Found a card!");
    for (uint8_t i=0; i < uidLength; i++) 
    {
     // Serial.print(" 0x");Serial.print(uid[i], HEX); 
    }
    }
  else
  {
    // PN532 probably timed out waiting for a card
    Serial.println("Timed out waiting for a card");
  }
  delay(1000);
if (powerpinRead == HIGH && prevpowerpinRead == LOW && millis() - time > debounce) 
  {
    if (powerpinState == HIGH)
    powerpinState = LOW;
        else
        powerpinState = HIGH;
        time = millis();    
  }
    digitalWrite(powerPin, powerpinState);
    
    prevpowerpinRead = powerpinRead;
  
  if (powerpinState == HIGH|| powerpinState == 0x11)
  
  {
  
  RTCNow(); 
  }
  Serial.println (powerpinState);
}

void RTCNow()
{
 DateTime now = rtc.now();
  if (secs == now.second())//do more for hrs etc to save time
  {
    return;
  }
  secs = now.second();
   
  tft.setTextColor(WHITE);
  tft.setTextSize(2);
  tft.setCursor(12,7);
  tft.print("  Clock ");
  tft.setTextSize(2);
  tft.setTextColor(MAGENTA, BLACK);
  tft.setCursor(15, 25);
  if ( now.hour()<10 ) tft.print(" ");
  tft.print(now.hour(), DEC);
  tft.print(":");
  if ( now.minute()<10 ) tft.print("0");
  tft.print(now.minute(), DEC);
  tft.print(":");

  if ( secs <10 ) tft.print("0");//previously uses second.now()but this should speed it up?
  tft.print(secs, DEC);
 

  tft.setTextSize(1);
  tft.setCursor(30, 45);
  tft.print(now.day(), DEC);
  tft.print("-");
  tft.print(now.month(), DEC);
  tft.print("-");
  tft.print(now.year(), DEC);
  tft.setCursor(17, 55);
  tft.setTextSize(2);
  tft.setTextColor(GREEN, BLACK);
  tft.print(daysOfTheWeek[now.dayOfTheWeek()]);
  tft.print("   "); // erase any previous date string that was longer
}
3

I have added a Serial.print into the RTCNow code to show the RTC seconds so I can see the RTC code is running from the loop, it just isnt displaying. I've also added a RTC test into the sketch to check its running as well and its fine,

RTC is on I2C (20/21) on mega.

full code is;

#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1351.h>
#include <PN532_SPI.h>
#include "PN532.h"
#include "RTClib.h"
PN532_SPI pn532spi(SPI, 10);
PN532 nfc(pn532spi);
RTC_DS3231 rtc;

#define dc   A2 
#define cs   53
#define rst  4

#define BLACK           0x0000
#define BLUE            0x001F
#define RED             0xF800
#define GREEN           0x07E0
#define CYAN            0x07FF
#define MAGENTA         0xF81F
#define YELLOW          0xFFE0  
#define WHITE           0xFFFF

Adafruit_SSD1351 tft = Adafruit_SSD1351(cs, dc, rst);
boolean success;
String cardNum;
//unsigned long RFID;
int powerPin = 13;//was 3
int powerpinRead;
int prevpowerpinRead = LOW;
int powerpinState = LOW;
long time = 0;         
long debounce = 200;   
float p = 3.1415926;
char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"};
uint8_t secs = 0;

void setup(void) {
 Serial.begin(9600);
 
  tft.begin();
  tft.fillRect(0, 0, 128, 128, BLACK);
  tft.setCursor(30, 5);
  tft.setTextColor(WHITE);
  tft.setTextSize(2);
  tft.println("Suzuki");
  tft.setTextSize(4);
  tft.println(" 112");
  delay (2000);
 //  tft.fillRect(0, 0, 128, 128, BLACK);

tft.fillScreen(BLACK);
  if (! rtc.begin()) {
    Serial.println("Couldn't find RTC");
    while (1);
  }

  rtc.adjust(DateTime(__DATE__, __TIME__));
  tft.setTextColor(WHITE);
  tft.setTextSize(2);
  tft.setCursor(0, 5);
  tft.print("  Clock ");
  delay(3000);
  tft.fillScreen(BLACK);
 
 nfc.begin();
uint32_t versiondata = nfc.getFirmwareVersion();
  if (! versiondata) {
  Serial.print("Didn't find PN53x board");
  while (1); // halt
  }
  nfc.setPassiveActivationRetries(0x01);
  nfc.SAMConfig();
   
  pinMode(powerPin, OUTPUT); 

 uint16_t time = millis();
 // tft.fillRect(0, 0, 128, 128, BLACK);
  time = millis() - time;


 
 
 }
void loop() 
{
 Serial.println ("loop running");
 RTCNow(); 
 readRfid();
 powerpinRead = (success);
 

 
}

void readRfid()
{
  
  uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 };  // Buffer to store the returned UID
  uint8_t uidLength;                        // Length of the UID (4 or 7 bytes depending on ISO14443A card type)
  success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, &uid[0], &uidLength);
  if (success) {
    //Serial.println(success);
    Serial.println("Found a card!");
    for (uint8_t i=0; i < uidLength; i++) 
    {
     // Serial.print(" 0x");Serial.print(uid[i], HEX); 
    }
    }
  else
  {
    // PN532 probably timed out waiting for a card
    Serial.println("Timed out waiting for a card");
  }
  delay(1000);
if (powerpinRead == HIGH && prevpowerpinRead == LOW && millis() - time > debounce) 
  {
    if (powerpinState == HIGH)
    powerpinState = LOW;
        else
        powerpinState = HIGH;
        time = millis();    
  }
    digitalWrite(powerPin, powerpinState);
    
    prevpowerpinRead = powerpinRead;
  
  if (powerpinState == HIGH|| powerpinState == 0x11)
  
  {
  
  //RTCNow(); 
  }
  Serial.println (powerpinState);
  
}

void RTCNow()
{
 DateTime now = rtc.now();
  
  tft.setTextSize(2);
  tft.setTextColor(MAGENTA, BLACK);
  tft.setCursor(0, 0);
  if ( now.hour()<10 ) tft.print(" ");
  tft.print(now.hour(), DEC);
  tft.print(":");
  if ( now.minute()<10 ) tft.print("0");
  tft.print(now.minute(), DEC);
  tft.print(":");
 if (secs == now.second())//do more of these IF's to save time on days and hours etc. not printing
  {
    return;
   
  }
   secs = now.second();
  if ( now.second()<10 ) tft.print("0");
  tft.print(now.second(), DEC);

  tft.setTextSize(1);
  tft.setCursor(0, 18);
  tft.print(now.day(), DEC);
  tft.print("-");
  tft.print(now.month(), DEC);
  tft.print("-");
  tft.print(now.year(), DEC);
  tft.setCursor(0, 30);
  tft.print(daysOfTheWeek[now.dayOfTheWeek()]);
  tft.print("   "); // erase any previous date string that was longer
  Serial.println (secs);//test
}