Week 10: Output devices

error: #error "This platform isn't recognized by FastLED... yet.  See comments in FastLED/led_sysdefs.h for options."

The ATtiny1614 generic board

At that point I decided to make an ATtiny1614 generic board, so I could control the OLED display and other devices. The board will have UPDI and FTDI interfaces, and 8 input/output pins, along with VCC and GND on every connector. Also a LED to check power and a capacitor to filter high frequencies and stabilize the power supply.

I like to have GND all around the circuit, so it's easier to connect everything to it, and the MCU in the center:

Eagle file is here.

PCB .png is here.

Outlines .png is here

As I was at home, I used the Genmitsu 3018 ProVer to make the board. This time I had it well calibrated and with a setup I knew it was going to work:

A cut depth of 0.1 mm, a "simulated" end mill of 0.65 mm (I was using a V-shaped mill) and a feed rate of 70 mm/min. 

The result was a pretty good board:

Using Atmel ICE to program the 1614 board

This time I hadn't the programmer we have at the lab, so I think it could be programmed by the Atmel-ICE. To power to the board I used a power supply of 5V. The most difficult thing for me was to set the correct pins of the UPDI interface on the Atmel ICE side:

After that I programmed the board with the simple led-blinking program and it worked well. So I tried to program the OLED display. I connected VCC, GND, SCL and SDA and programmed it with a "Hello world" program, but nothing happened. Then I changed the adress of the I2C interface from 0x3C to 03D, and even 0x78, because the last one was printed on the OLED display as the I2C address. Nothing. 

Then I used a program to scan I2C address:

// I2C address scanner program
#include <Wire.h>

void setup()
{
  Wire.begin();
  Serial.begin(9600);
  Serial.println("I2C Scanner");
}

void loop()
{
  byte error, address;
  int nDevices;

  Serial.println("Scanning...");

  nDevices = 0;
  for(address = 1; address < 127; address++ )
  {
    Wire.beginTransmission(address);
    error = Wire.endTransmission();

    if (error == 0)
    {
      Serial.print("I2C device found at address 0x");
      if (address < 16)
        Serial.print("0");

      Serial.print(address,HEX);
      Serial.println("  !");

      nDevices++;
    }
    else if (error==4)
    {
      Serial.print("Unknown error at address 0x");
      if (address < 16)
        Serial.print("0");

      Serial.println(address,HEX);
    }
  }

  if (nDevices == 0)
    Serial.println("No I2C devices found");
  else
    Serial.println("done");

  delay(5000); // wait 5 seconds for next scan
}

But the scanner couldn't find any device. So I thought perhaps the OLED display was wrong. As it was Sunday I decided to try another display on monday morning. 

When I arrived at the lab I tried another OLED display and I worked without problems. This is the hello program I used:

#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

void setup() {
  Serial.begin(115200);

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }
  delay(2000);
  display.clearDisplay();

  display.setTextSize(1);
  display.setTextColor(WHITE);
  display.setCursor(0, 10);
  // Display static text
  display.println("Hello, world!");
   display.println("Fab Academy 2022");
   display.println("Jon Merino");
  display.display(); 
}

void loop() {
  
}