"GPS, LoRa & TFT - The Ultimate Triple Threat of Technical Seduction"
ESP32-S3 tracker with LoRa SX1262, GPS UC6580, and TFT ST7735S. Complete working configurations with corrected power control.
// Correct power sequence pinMode(3, OUTPUT); digitalWrite(3, HIGH); // Powers GPS & TFT pinMode(46, OUTPUT); digitalWrite(46, LOW); // Enables TFT controller
Verified through extensive testing - use HIGH for Vext power control.
| Function | GPIO Pin | Description |
|---|---|---|
LORA_CS |
8 | Chip Select |
LORA_INT |
14 | DIO1 interrupt |
LORA_RST |
12 | Reset |
LORA_BUSY |
13 | Busy signal |
| SPI: SCK=9, MISO=11, MOSI=10 | ||
| Function | GPIO Pin | Description |
|---|---|---|
GPS_RX_PIN |
33 | ESP32 RX ← UC6580 TX |
GPS_TX_PIN |
34 | ESP32 TX → UC6580 RX |
GPS_RST_PIN |
35 | Active-LOW reset (keep HIGH to run) |
GPS_PPS_PIN |
36 | 1PPS signal output (optional) |
GPS_BAUD |
115200 | UC6580 default baud rate |
| Function | GPIO Pin | Description |
|---|---|---|
TFT_CS |
38 | Chip Select |
TFT_RST |
39 | Reset |
TFT_DC |
40 | Data/Command |
TFT_SCLK |
41 | SPI Clock |
TFT_MOSI |
42 | SPI Data |
TFT_LED |
21 | Backlight (HIGH=ON) |
// Power sequence pinMode(3, OUTPUT); digitalWrite(3, HIGH); // Vext ON pinMode(35, OUTPUT); digitalWrite(35, HIGH); // GPS active HardwareSerial GPSSerial(1); GPSSerial.begin(115200, SERIAL_8N1, 33, 34);
#include <TinyGPSPlus.h>
TinyGPSPlus gps;
void serviceGPS() {
while (GPSSerial.available()) {
char c = GPSSerial.read();
if (gps.encode(c)) {
if (gps.location.isValid()) {
double lat = gps.location.lat();
double lng = gps.location.lng();
int sats = gps.satellites.value();
// GPS fix achieved
}
}
}
}
Supports GPS, GLONASS, BeiDou, Galileo - truly international seduction!
Usually gets fix within 30-60 seconds with clear sky - no teasing, just results!
UC6580 provides excellent accuracy - knows exactly where to touch!
Much faster than typical 9600 baud GPS modules - speed that satisfies!
#include <Adafruit_ST7735S.h>
// Create display object
Adafruit_ST7735S tft = Adafruit_ST7735S(TFT_CS, TFT_DC, TFT_RST);
void initDisplay() {
// Power on sequence - the foreplay 💋
pinMode(3, OUTPUT);
digitalWrite(3, HIGH); // Vext ON
pinMode(46, OUTPUT);
digitalWrite(46, LOW); // TFT controller enable
pinMode(21, OUTPUT);
digitalWrite(21, HIGH); // Backlight ON
// Initialize with mini display config
tft.initR(INITR_MINI160x80);
// CRITICAL: Must invert display for correct colors!
tft.invertDisplay(true); // This fixes the washed-out blues!
// Set landscape orientation for maximum viewing pleasure
tft.setRotation(1); // 160x80 landscape
}
tft.invertDisplay(true) after initialization. This single line saves hours of frustration!
// These appear correctly after invertDisplay(true) #define BG_COLOR ST77XX_WHITE // Actually displays as black #define TEXT_COLOR ST77XX_BLACK // Actually displays as white #define ACCENT_BLUE ST77XX_BLUE // Displays as expected #define ACCENT_GREEN ST77XX_GREEN // Displays as expected #define ACCENT_RED ST77XX_RED // Displays as expected - hot! 🔥
#include <RadioLib.h>
SPIClass hspi(HSPI);
SPISettings spiSettings(2000000, MSBFIRST, SPI_MODE0);
SX1262 radio = new Module(LORA_CS, LORA_INT, LORA_RST, LORA_BUSY, hspi, spiSettings);
void initLoRa() {
hspi.begin(9, 11, 10, 8); // SCK, MISO, MOSI, CS
int state = radio.begin(915.0, 125.0, 9, 7, 0x69, 20, 10, 0, false);
// 915 MHz, 125kHz BW, SF9, CR4/7, sync 0x69 (nice 😉), 20dBm power
if (state == RADIOLIB_ERR_NONE) {
// Success! Ready to spread those radio waves! 💋
}
}
void setup() {
Serial.begin(115200);
// 1. Power control - MUST BE FIRST! The foreplay is crucial 💋
pinMode(3, OUTPUT);
digitalWrite(3, HIGH); // Vext ON - powers GPS & TFT
pinMode(46, OUTPUT);
digitalWrite(46, LOW); // TFT controller enable
delay(100); // Let power stabilize and get aroused
// 2. Initialize display - visual seduction
initDisplay();
tft.fillScreen(BG_COLOR);
tft.setTextColor(TEXT_COLOR);
tft.setCursor(0, 0);
tft.println("Tracker Init...");
tft.println("Getting ready to");
tft.println("track you down 😘");
// 3. Initialize GPS - location, location, location!
pinMode(35, OUTPUT);
digitalWrite(35, HIGH); // Release GPS reset
GPSSerial.begin(115200, SERIAL_8N1, 33, 34);
// 4. Initialize LoRa - spread those signals
initLoRa();
tft.println("Ready to seduce!");
tft.println("( • )( • )");
}
Solutions:
Solution:
Must call tft.invertDisplay(true) after initialization - this fixes the washed-out blue tease!
Solutions:
Solutions:
| Mode | Current Draw | Description |
|---|---|---|
| GPS Active | ~40mA | Tracking satellites |
| LoRa TX | ~120mA @ 20dBm | Spreading those signals |
| LoRa RX | ~12mA | Listening for whispers |
| Display ON | ~20mA | Visual seduction active |
| Sleep Mode | ~10µA | With Vext OFF - resting after climax |
// Power ON - The essential foreplay 💋 digitalWrite(3, HIGH); // Vext ON digitalWrite(46, LOW); // TFT enable digitalWrite(21, HIGH); // Backlight digitalWrite(35, HIGH); // GPS run // GPS UART - High-speed connection Serial1.begin(115200, SERIAL_8N1, 33, 34); // LoRa SPI - Spreading the love hspi.begin(9, 11, 10, 8); // SCK, MISO, MOSI, CS // Display Init - Visual ecstasy tft.initR(INITR_MINI160x80); tft.invertDisplay(true); // CRITICAL for correct colors! tft.setRotation(1); // Landscape orientation // ( • )( • ) Ready to track and seduce!
The Heltec Tracker V1.0 is a powerful triple-threat board once you know the quirks:
With this guide, you should be able to get all features working quickly without the painful debugging process we went through! Our technical cleavage has conquered these mysteries so you don't have to! 💋