I am converting an old RGB controller to an ESP8266 WLED WS2812 Controller. I removed the power transistors and cut the runs for the pull up resistors (Just to the left of the large pads where the power transistors were). I tapped into the 5V buss at the top and the ground was available on a pin on the power transistors as marked in the picture. D1 D2 D3 go to the large solder pads where the power transistors were mountd. I should have used resistors for the D1-D3 lines.
Tuesday, November 28, 2023
Converting RGB controller to ESP8266 WLED Ws2812 Controller.
Wednesday, November 1, 2023
MLX90640 and ESP32 Thermal Imaging Camera with 2.8" TFT SPI
I decided to update my old thermal imaging camera. Back in 2020 I had built a AMG8833 based camera. Its resolution was only 8x8 pixels. The MLX90640 is 32x24 pixels, that is a huge improvement for about $40. I was hoping that I could just unplug the one sensor and plug in the new one. Things are never that simple!
This is a picture of the completed project. The camera does not do a good job. I tried multiple cameras and they all fail to show the varying shades of colors! BTW that is me holding the camera.
I could not get the sparkfun MLX90640 library to load or run. That was desired to be able to use some software already available on the web. So I was stuck with the Adafruit library that was easily installed within the Arduino IDE. But I had to write my own interface for the LCD screen. Then I added the screen support to the simpletest program instead of sending the results to the serial port. Make sure you also install the ILI9341 driver within the Arduino IDE.
Connections:
LCD:
26=C/D
18=SCK
19=MISO
23=MOSI
5=CS0
3.3V=VCC,RES,LED (Jumpered on display)
GND=GND
MLX90640
22=SCL
21=SDA
3.3V=VIN
GND=GND
Here is my code:
#include <Adafruit_MLX90640.h>
#include "Adafruit_GFX.h"
#include "Adafruit_ILI9341.h"
#include "SPI.h"
#define PRINT_ASCIIART
// Use the default pins for all but:
#define TFT_CS 5
#define TFT_DC 26
Adafruit_ILI9341 tft = Adafruit_ILI9341(TFT_CS, TFT_DC);
Adafruit_MLX90640 mlx;
float frame[32*24]; // buffer for full frame of temperatures
int r,g,b;
void setup() {
Serial.begin(115200);
delay(100);
if (! mlx.begin(MLX90640_I2CADDR_DEFAULT, &Wire)) {
Serial.println("MLX90640 not found!");
while (1) delay(10);
}
Serial.println("Found Adafruit MLX90640");
Serial.print("Serial number: ");
Serial.print(mlx.serialNumber[0], HEX);
Serial.print(mlx.serialNumber[1], HEX);
Serial.println(mlx.serialNumber[2], HEX);
mlx.setMode(MLX90640_CHESS);
mlx.setResolution(MLX90640_ADC_18BIT);
mlx.setRefreshRate(MLX90640_2_HZ);
// Screen setup
tft.begin();
tft.setRotation(3);
tft.fillScreen(ILI9341_BLACK);
tft.setTextSize(2);
}
void loop() {
if (mlx.getFrame(frame) != 0) {
Serial.println("Failed");
return; }
// determine the ranges
int maxt=0;
int mint=255;
for (uint8_t h = 0; h < 24; h++) {
for (uint8_t w = 0; w < 32; w++) {
int t = frame[h*32 + w];
if (t > maxt) maxt=t ;
if (t < mint) mint=t ;
}
}
tft.setCursor(0, 210);
tft.print("IR Camera Max Temp: ");
tft.fillRect(230, 210, 32, 16, ILI9341_BLACK );
tft.setCursor(230, 210);
tft.print(maxt);
// drawing the picture
for (uint8_t h = 0; h < 24; h++) {
for (uint8_t w = 0; w < 32; w++) {
int t = frame[h*32 + w];
r=0; g=0; b=0;
int t2= map(t, mint, maxt, 0, 255);
if (t2 > 70) r = t2+120;
if (r > 255) r=255;
if (t2 > 130) g = t2; // Highlight higher temps
if (t2 < 70) b = 255-t2; // More blue=colder
tft.fillRect(w * 8, h * 8, 8, 8, tft.color565(r, g, b));
}
}
}
Here are several views of the completed wiring if you need something to compare yours to.