Issue with ssd1306 128x64 displays on the TEENSY3.x

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On the attached photo you can see the backsides of two 128x64 displays with 
ssd1306 controller.
The display color of the right one is white and the color of the left one is 
yellow/blue.
Both displays are working with hardware SPI on the ARDUINO DUE, but only the 
white ones (on the right of the photo) are working with the TEENSY3.0! I tried 
it with software SPI (native u8glib) and an own com procedure for hardware SPI, 
but only the white displays (I tested several displays of both types) are 
working on the Teensy3.0!? I'am very confused now!

For the sake of completeness here's my com procedure for hw SPI on the 
TEENSY3.0 (it's a slightly modified version of this port: 
https://github.com/FriedCircuits/Ug8lib_Teensy):


#if defined(__MK20DX256__)|| defined(__MK20DX128__) 
#include <Arduino.h>
#include "u8glib.h"
#include <SPI.h>

uint8_t u8g_com_hw_spi_fn1(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void 
*arg_ptr)
{
  switch(msg)
  {
    case U8G_COM_MSG_STOP:
      //STOP THE DEVICE
    break;

    case U8G_COM_MSG_INIT:
        //INIT HARDWARE INTERFACES, TIMERS, GPIOS...
        pinMode(3, OUTPUT);
        //For hardware SPI
        pinMode(10, OUTPUT);
        SPI.begin();
        SPI.setClockDivider(SPI_CLOCK_DIV2);


        pinMode(2, OUTPUT);
        digitalWrite(2, HIGH);
        // VDD (3.3V) goes high at start, lets just chill for a ms
        delay(1);
        // bring reset low
        digitalWrite(2, LOW);
        // wait 10ms
        delay(10);
        // bring out of reset
        digitalWrite(2, HIGH);

        //pinMode(MOSI, OUTPUT);
        //pinMode(SCK, OUTPUT);

        /*
        clkport     = portOutputRegister(digitalPinToPort(SCK));
        clkpinmask  = digitalPinToBitMask(SCK);
        mosiport    = portOutputRegister(digitalPinToPort(MOSI));
        mosipinmask = digitalPinToBitMask(MOSI);
        csport      = portOutputRegister(digitalPinToPort(10));
        cspinmask   = digitalPinToBitMask(10);
        dcport      = portOutputRegister(digitalPinToPort(3));
        dcpinmask   = digitalPinToBitMask(3);
        */

    break;

    case U8G_COM_MSG_ADDRESS:  
      //SWITCH FROM DATA TO COMMAND MODE (arg_val == 0 for command mode)
      if (arg_val != 0)
      {
          digitalWrite(3, HIGH);
      }
      else
      {
          digitalWrite(3, LOW);
      }

    break;

    case U8G_COM_MSG_CHIP_SELECT:
        if(arg_val == 0)
        {
            digitalWrite(10, HIGH);
        }
        else{
            digitalWrite(10, LOW);
        }
    break;

    case U8G_COM_MSG_RESET:
      //TOGGLE THE RESET PIN ON THE DISPLAY BY THE VALUE IN arg_val
      digitalWrite(2, arg_val);
    break;

    case U8G_COM_MSG_WRITE_BYTE:
      //WRITE BYTE TO DEVICE
      SPI.transfer(arg_val);

    break;

    case U8G_COM_MSG_WRITE_SEQ:
    case U8G_COM_MSG_WRITE_SEQ_P:
    {
      //WRITE A SEQUENCE OF BYTES TO THE DEVICE
      register uint8_t *ptr = static_cast<uint8_t *>(arg_ptr);
      while(arg_val > 0){
        SPI.transfer(*ptr++);
        arg_val--;
      }
     }
    break;

  }
  return 1;
}
#endif

Original issue reported on code.google.com by [email protected] on 8 May 2015 at 8:02

Attachments:

• ssd1306_128x64_.jpg