This week, we learned about output devices, including the buzzer (which I am a bit familiar with now), the tft display, and led strips. The assignment for this week was to build something along the lines of what I ended up making for last week, so I am going to use what I learned from that experience with a new output device.
To do this, I again planned to use my hall sensor for magnetism, and its corresponding calibration curve from last week. For more details about that process, feel free to look at week 6's post. Recall that this sensor has an added layer for calibration, where my magnet will bring the sensor value either down to 10 or up to 1000 from the standard 500 value depending on which side of the magnet is exposed to the sensor. For calibration purposes, I decided to only calibrate for the bottom half of my range, as the graph for the upper half would be a mirror image of the lower half. In this project, I decided to explore the full range of magnet values with a tft display.
Before I could play with the hall sensor input, I needed to get the tft display working. I followed the tutorial from the PS70 website, changing a few pins for the Metro M0 boards that we used based on the results of my classmates. (Shout out to Samantha for her super helpful wiring writeup!) Once I had the tft setup, I ran the code from the tutorial to test the screen's capabilities. It ended up working perfectly! With the screen setup, I could finally connect my hall sensor and begin changing the colors based on the magnet's position.
One major drawback of my project from last week was the shoddy pitch range I could create with the magnet. As the calibration curve shows, this sensor has a very short height range of value change, and that change is not linear. Thus, as I move linearly with my magnet, the pitch of my buzzer would settle on this higher tone quite quickly. To correct for this, I wrote a new mapping function that would try to spread this movement over a greater range to create what will hopefully be a smoother transition on my tft display. With this function working, I could finally assemble the pieces. For my display, I rigged my hall sensor up to the breadboard in the same way as I did in week six. My only change electronically was to connect all of my ground pins to the negative thread on the breadboard before using a single ground pin on my board, and the same with my power pins on the positive rail.
I then modified the test script from the tutorial by assigning a variable in the loop to hold the sensor value, passing that sensor value into the mapping function, and using that mapped result as a color factor for my image display. I am pretty happy with the final reuslt. The colors don't turn out as vibrant on the video I recorded as they do in real life, but I hope you still enjoy!
/**************************************************************************
This is a library for several Adafruit displays based on ST77* drivers.
Works with the Adafruit 1.8" TFT Breakout w/SD card
----> http://www.adafruit.com/products/358
The 1.8" TFT shield
----> https://www.adafruit.com/product/802
The 1.44" TFT breakout
----> https://www.adafruit.com/product/2088
The 1.14" TFT breakout
----> https://www.adafruit.com/product/4383
The 1.3" TFT breakout
----> https://www.adafruit.com/product/4313
The 1.54" TFT breakout
----> https://www.adafruit.com/product/3787
The 2.0" TFT breakout
----> https://www.adafruit.com/product/4311
as well as Adafruit raw 1.8" TFT display
----> http://www.adafruit.com/products/618
Check out the links above for our tutorials and wiring diagrams.
These displays use SPI to communicate, 4 or 5 pins are required to
interface (RST is optional).
Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!
Written by Limor Fried/Ladyada for Adafruit Industries.
MIT license, all text above must be included in any redistribution
**************************************************************************/
#include // Core graphics library
#include // Hardware-specific library for ST7735
#include // Hardware-specific library for ST7789
#include
#if defined(ARDUINO_FEATHER_ESP32) // Feather Huzzah32
#define TFT_CS 14
#define TFT_RST 15
#define TFT_DC 32
#elif defined(ESP8266)
#define TFT_CS 4
#define TFT_RST 16
#define TFT_DC 5
#else
// For the breakout board, you can use any 2 or 3 pins.
// These pins will also work for the 1.8" TFT shield.
#define TFT_CS 10
#define TFT_RST 9 // Or set to -1 and connect to Arduino RESET pin
#define TFT_DC 8
#endif
// OPTION 1 (recommended) is to use the HARDWARE SPI pins, which are unique
// to each board and not reassignable. For Arduino Uno: MOSI = pin 11 and
// SCLK = pin 13. This is the fastest mode of operation and is required if
// using the breakout board's microSD card.
// For 1.44" and 1.8" TFT with ST7735 use:
//Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);
// For 1.14", 1.3", 1.54", and 2.0" TFT with ST7789:
Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_RST);
// OPTION 2 lets you interface the display using ANY TWO or THREE PINS,
// tradeoff being that performance is not as fast as hardware SPI above.
//#define TFT_MOSI 11 // Data out
//#define TFT_SCLK 13 // Clock out
// For ST7735-based displays, we will use this call
//Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCLK, TFT_RST);
// OR for the ST7789-based displays, we will use this call
//Adafruit_ST7789 tft = Adafruit_ST7789(TFT_CS, TFT_DC, TFT_MOSI, TFT_SCLK, TFT_RST);
float p = 3.1415926;
int period = 5;
unsigned long time_now = 0;
void setup(void) {
Serial.begin(9600);
Serial.print(F("Hello! ST77xx TFT Test"));
// Use this initializer if using a 1.8" TFT screen:
//tft.initR(INITR_BLACKTAB); // Init ST7735S chip, black tab
// OR use this initializer if using a 1.8" TFT screen with offset such as WaveShare:
// tft.initR(INITR_GREENTAB); // Init ST7735S chip, green tab
// OR use this initializer (uncomment) if using a 1.44" TFT:
//tft.initR(INITR_144GREENTAB); // Init ST7735R chip, green tab
// OR use this initializer (uncomment) if using a 0.96" 160x80 TFT:
//tft.initR(INITR_MINI160x80); // Init ST7735S mini display
// OR use this initializer (uncomment) if using a 1.3" or 1.54" 240x240 TFT:
//tft.init(240, 240); // Init ST7789 240x240
// OR use this initializer (uncomment) if using a 2.0" 320x240 TFT:
//tft.init(240, 320); // Init ST7789 320x240
// OR use this initializer (uncomment) if using a 1.14" 240x135 TFT:
tft.init(135, 240); // Init ST7789 240x135
// SPI speed defaults to SPI_DEFAULT_FREQ defined in the library, you can override it here
// Note that speed allowable depends on chip and quality of wiring, if you go too fast, you
// may end up with a black screen some times, or all the time.
//tft.setSPISpeed(40000000);
Serial.println(F("Initialized"));
uint16_t time = millis();
tft.fillScreen(ST77XX_BLACK);
time = millis() - time;
Serial.println(time, DEC);
time_now = millis();
while (millis() < time_now + 500) {}
// large block of text
tft.fillScreen(ST77XX_BLACK);
testdrawtext("Lorem ipsum dolor sit amet, consectetur adipiscing elit. Curabitur adipiscing ante sed nibh tincidunt feugiat. Maecenas enim massa, fringilla sed malesuada et, malesuada sit amet turpis. Sed porttitor neque ut ante pretium vitae malesuada nunc bibendum. Nullam aliquet ultrices massa eu hendrerit. Ut sed nisi lorem. In vestibulum purus a tortor imperdiet posuere. ", ST77XX_WHITE);
time_now = millis();
while (millis() < time_now + 1000) {};
// tft print function!
tftPrintTest();
time_now = millis();
while (millis() < time_now + 4000) {};
// a single pixel
tft.drawPixel(tft.width()/2, tft.height()/2, ST77XX_GREEN);
time_now = millis();
while (millis() < time_now + 500) {}
// line draw test
testlines(ST77XX_YELLOW);
time_now = millis();
while (millis() < time_now + 500) {}
// optimized lines
testfastlines(ST77XX_RED, ST77XX_BLUE);
time_now = millis();
while (millis() < time_now + 500) {}
testdrawrects(ST77XX_GREEN);
time_now = millis();
while (millis() < time_now + 500) {}
testfillrects(ST77XX_YELLOW, ST77XX_MAGENTA);
time_now = millis();
while (millis() < time_now + 500) {}
tft.fillScreen(ST77XX_BLACK);
testfillcircles(10, ST77XX_BLUE);
testdrawcircles(10, ST77XX_WHITE);
time_now = millis();
while (millis() < time_now + 500) {}
testroundrects();
time_now = millis();
while (millis() < time_now + 500) {}
testtriangles();
time_now = millis();
while (millis() < time_now + 500) {}
}
void loop() {
int sensorValue = analogRead(A0);
int color = map(sensorValue, 0, 1100, 0, 255);
tft.fillScreen(tft.color565((255 - color), 0, color));
time_now = millis();
while (millis() < time_now + period) {}
}
void testlines(uint16_t color) {
tft.fillScreen(ST77XX_BLACK);
for (int16_t x=0; x < tft.width(); x+=6) {
tft.drawLine(0, 0, x, tft.height()-1, color);
time_now = millis();
while (millis() < time_now) {}
}
for (int16_t y=0; y < tft.height(); y+=6) {
tft.drawLine(0, 0, tft.width()-1, y, color);
time_now = millis();
while (millis() < time_now) {}
}
tft.fillScreen(ST77XX_BLACK);
for (int16_t x=0; x < tft.width(); x+=6) {
tft.drawLine(tft.width()-1, 0, x, tft.height()-1, color);
time_now = millis();
while (millis() < time_now) {}
}
for (int16_t y=0; y < tft.height(); y+=6) {
tft.drawLine(tft.width()-1, 0, 0, y, color);
time_now = millis();
while (millis() < time_now) {}
}
tft.fillScreen(ST77XX_BLACK);
for (int16_t x=0; x < tft.width(); x+=6) {
tft.drawLine(0, tft.height()-1, x, 0, color);
time_now = millis();
while (millis() < time_now) {}
}
for (int16_t y=0; y < tft.height(); y+=6) {
tft.drawLine(0, tft.height()-1, tft.width()-1, y, color);
time_now = millis();
while (millis() < time_now) {}
}
tft.fillScreen(ST77XX_BLACK);
for (int16_t x=0; x < tft.width(); x+=6) {
tft.drawLine(tft.width()-1, tft.height()-1, x, 0, color);
time_now = millis();
while (millis() < time_now) {}
}
for (int16_t y=0; y < tft.height(); y+=6) {
tft.drawLine(tft.width()-1, tft.height()-1, 0, y, color);
time_now = millis();
while (millis() < time_now) {}
}
}
void testdrawtext(char *text, uint16_t color) {
tft.setCursor(0, 0);
tft.setTextColor(color);
tft.setTextWrap(true);
tft.print(text);
}
void testfastlines(uint16_t color1, uint16_t color2) {
tft.fillScreen(ST77XX_BLACK);
for (int16_t y=0; y < tft.height(); y+=5) {
tft.drawFastHLine(0, y, tft.width(), color1);
}
for (int16_t x=0; x < tft.width(); x+=5) {
tft.drawFastVLine(x, 0, tft.height(), color2);
}
}
void testdrawrects(uint16_t color) {
tft.fillScreen(ST77XX_BLACK);
for (int16_t x=0; x < tft.width(); x+=6) {
tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color);
}
}
void testfillrects(uint16_t color1, uint16_t color2) {
tft.fillScreen(ST77XX_BLACK);
for (int16_t x=tft.width()-1; x > 6; x-=6) {
tft.fillRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color1);
tft.drawRect(tft.width()/2 -x/2, tft.height()/2 -x/2 , x, x, color2);
}
}
void testfillcircles(uint8_t radius, uint16_t color) {
for (int16_t x=radius; x < tft.width(); x+=radius*2) {
for (int16_t y=radius; y < tft.height(); y+=radius*2) {
tft.fillCircle(x, y, radius, color);
}
}
}
void testdrawcircles(uint8_t radius, uint16_t color) {
for (int16_t x=0; x < tft.width()+radius; x+=radius*2) {
for (int16_t y=0; y < tft.height()+radius; y+=radius*2) {
tft.drawCircle(x, y, radius, color);
}
}
}
void testtriangles() {
tft.fillScreen(ST77XX_BLACK);
uint16_t color = 0xF800;
int t;
int w = tft.width()/2;
int x = tft.height()-1;
int y = 0;
int z = tft.width();
for(t = 0 ; t <= 15; t++) {
tft.drawTriangle(w, y, y, x, z, x, color);
x-=4;
y+=4;
z-=4;
color+=100;
}
}
void testroundrects() {
tft.fillScreen(ST77XX_BLACK);
uint16_t color = 100;
int i;
int t;
for(t = 0 ; t <= 4; t+=1) {
int x = 0;
int y = 0;
int w = tft.width()-2;
int h = tft.height()-2;
for(i = 0 ; i <= 16; i+=1) {
tft.drawRoundRect(x, y, w, h, 5, color);
x+=2;
y+=3;
w-=4;
h-=6;
color+=1100;
}
color+=100;
}
}
void tftPrintTest() {
tft.setTextWrap(false);
tft.fillScreen(ST77XX_BLACK);
tft.setCursor(0, 30);
tft.setTextColor(ST77XX_RED);
tft.setTextSize(1);
tft.println("Hello World!");
tft.setTextColor(ST77XX_YELLOW);
tft.setTextSize(2);
tft.println("Hello World!");
tft.setTextColor(ST77XX_GREEN);
tft.setTextSize(3);
tft.println("Hello World!");
tft.setTextColor(ST77XX_BLUE);
tft.setTextSize(4);
tft.print(1234.567);
time_now = millis();
while (millis() < time_now + 1500) {}
tft.setCursor(0, 0);
tft.fillScreen(ST77XX_BLACK);
tft.setTextColor(ST77XX_WHITE);
tft.setTextSize(0);
tft.println("Hello World!");
tft.setTextSize(1);
tft.setTextColor(ST77XX_GREEN);
tft.print(p, 6);
tft.println(" Want pi?");
tft.println(" ");
tft.print(8675309, HEX); // print 8,675,309 out in HEX!
tft.println(" Print HEX!");
tft.println(" ");
tft.setTextColor(ST77XX_WHITE);
tft.println("Sketch has been");
tft.println("running for: ");
tft.setTextColor(ST77XX_MAGENTA);
tft.print(millis() / 1000);
tft.setTextColor(ST77XX_WHITE);
tft.print(" seconds.");
}
© Lauren Cooke 2021