firmware/variants/nrf52840/t-echo-card/variant.h

// Variant definition for LilyGo T-Echo-Card (nRF52840)

#ifndef _VARIANT_T_ECHO_CARD_
#define _VARIANT_T_ECHO_CARD_

/** Master clock frequency */
#define VARIANT_MCK (64000000ul)

#define USE_LFXO // Board uses 32kHz crystal for LF

/*----------------------------------------------------------------------------
 *        Headers
 *----------------------------------------------------------------------------*/

#include "WVariant.h"

#ifdef __cplusplus
extern "C" {
#endif // __cplusplus

// Number of pins defined in PinDescription array
#define PINS_COUNT (48)
#define NUM_DIGITAL_PINS (48)
#define NUM_ANALOG_INPUTS (1)
#define NUM_ANALOG_OUTPUTS (0)

// LEDs - board only exposes 3x WS2812 addressable LEDs. No plain GPIO LEDs.
// Intentionally do not define PIN_LED1 on this variant, so nRF52 platform
// code does not auto-enable a nonexistent GPIO power/status LED.
#define LED_STATE_ON 1

// Three independent WS2812 data lines (one LED per line, not a daisy chain).
// Each is driven as a 1-pixel NeoPixel by StatusLEDModule / ExternalNotification,
// assigns LED_POWER (red) and LED_NOTIFICATION (green).
#define WS2812_DATA_1 (32 + 7)  // P1.7  - charge/heartbeat (red)
#define WS2812_DATA_2 (32 + 12) // P1.12 - external notification (green)
#define WS2812_DATA_3 (0 + 28)  // P0.28 - BLE pairing (blue)

// Wire each WS2812 to a status role. Colour defaults are scaled to 25%
// brightness (0x40) - the bare-die WS2812s on this board are very bright at
// full intensity in a close-range enclosure.
#define NEOPIXEL_STATUS_POWER_PIN WS2812_DATA_1
#define NEOPIXEL_STATUS_NOTIFICATION_PIN WS2812_DATA_2
#define NEOPIXEL_STATUS_PAIRING_PIN WS2812_DATA_3
#define NEOPIXEL_STATUS_POWER_COLOR 0x400000        // red   @ 25%
#define NEOPIXEL_STATUS_NOTIFICATION_COLOR 0x004000 // green @ 25%
#define NEOPIXEL_STATUS_PAIRING_COLOR 0x000040      // blue  @ 25%

// The charger IC does not blink on its own; let StatusLEDModule do the
// software blink while charging
// If left defined: hardware would be expected to handle the charging pulse.
// #define POWER_LED_HARDWARE_BLINKS_WHILE_CHARGING

// Buttons
#define PIN_BUTTON1 (32 + 10) // KEY_1: P1.10

// Second button, shares the bootloader's DFU pin (nRF52840_BOOT/P0.24) - safe to read
// as a normal GPIO once the app is running. Wired as literal DOWN (see DOWN_BUTTON_PIN
// in InputBroker.cpp), not ALT_BUTTON_PIN, since message/nodelist scroll needs UP/DOWN.
// Not named PIN_BUTTON2 - configuration.h auto-maps that to ALT_BUTTON_PIN (conflict).
#define PIN_BUTTON_DOWN (0 + 24) // nRF52840_BOOT
#define DOWN_BUTTON_PIN PIN_BUTTON_DOWN
#define DOWN_BUTTON_ACTIVE_LOW true
#define DOWN_BUTTON_ACTIVE_PULLUP true

#define BUTTON_CLICK_MS 400

// Analog pins
#define PIN_A0 (0 + 2) // Battery ADC (BATTERY_ADC_DATA)

#define BATTERY_PIN PIN_A0

static const uint8_t A0 = PIN_A0;

#define ADC_RESOLUTION 14

// BATTERY_MEASUREMENT_CONTROL - enable divider for battery reading
#define ADC_CTRL (0 + 31)
#define ADC_CTRL_ENABLED HIGH

// NFC placeholders, not used
#define PIN_NFC1 (9)
#define PIN_NFC2 (10)

// Wire Interfaces (IIC_1 on the vendor header)
#define WIRE_INTERFACES_COUNT 1

#define PIN_WIRE_SDA (32 + 4) // IIC_1_SDA: P1.4
#define PIN_WIRE_SCL (32 + 2) // IIC_1_SCL: P1.2

// ICM20948 IMU + magnetometer, same I2C bus as the OLED. Skips the generic auto-probe
// heuristic (register value can be misread as BMI270/MPU6050) and forces the known chip.
#define HAS_ICM20948

// External serial flash ZD25WQ32CEIGR
// QSPI Pins
#define PIN_QSPI_SCK (0 + 4)
#define PIN_QSPI_CS (0 + 12)
#define PIN_QSPI_IO0 (0 + 6)  // MOSI if using two bit interface
#define PIN_QSPI_IO1 (0 + 8)  // MISO if using two bit interface
#define PIN_QSPI_IO2 (32 + 9) // WP
#define PIN_QSPI_IO3 (0 + 26) // HOLD

// On-board QSPI Flash
#define EXTERNAL_FLASH_DEVICES ZD25WQ32CEIGR
#define EXTERNAL_FLASH_USE_QSPI

// Lora S62F (SX1262)
#define USE_SX1262
#define SX126X_CS (0 + 11)
#define SX126X_DIO1 (32 + 8)
#define SX126X_DIO2 (0 + 5)
#define SX126X_BUSY (0 + 14)
#define SX126X_RESET (0 + 7)
#define SX126X_RXEN (32 + 1) // SX1262_RF_VC2
#define SX126X_TXEN (0 + 27) // SX1262_RF_VC1
#define SX126X_DIO3_TCXO_VOLTAGE 1.8

// ───────────────────────────────────────────────────────────────────────────
// OLED display: SSD1315 on I2C @ 0x3C (IIC_1).
//
// Viewport: the physical panel is 72×40, mapped into the SSD1315's 128×64
// GDDRAM at columns 28..99, pages 3..7. The shared OLED driver centers the
// 72×40 framebuffer and applies the page offset.
// ───────────────────────────────────────────────────────────────────────────
#define HAS_SCREEN 1
#define USE_SSD1306
#define OLED_GEOMETRY_OVERRIDE GEOMETRY_72_40
#define OLED_Y_OFFSET_PAGES 3
#define SSD1306_WIRE_I2C_FREQUENCY 100000
#define OLED_TINY
#define OLED_COMPACT_UI // No header/nav bar - centered icon+title splash, full-screen content

// Controls power 3V3 for all peripherals (GPS + LoRa + Sensor)
#define PIN_POWER_EN (0 + 30) // RT9080_EN

// SPI1 is unused (no external SPI display). Keep declarations for the core.
#define PIN_SPI1_MISO (-1)
#define PIN_SPI1_MOSI (-1)
#define PIN_SPI1_SCK (-1)

// GPS pins
#define GPS_L76K
#define GPS_BAUDRATE 9600
#define HAS_GPS 1

#define PIN_GPS_EN (32 + 15)     // GPS_EN: P1.15 - GPS power enable
#define GPS_EN_ACTIVE LOW        // Active-low on this board, was wrongly HIGH
#define PIN_GPS_STANDBY (0 + 25) // GPS_WAKE_UP: P0.25 - wakeup pin
#define GPS_FORCE_SOFT_SLEEP     // Vendor firmware uses L76K standby rather than cycling its main rail
#define PIN_GPS_PPS (0 + 23)     // GPS_1PPS: P0.23
#define GPS_RX_PIN (0 + 19)      // MCU RX ← GPS's TX (vendor GPS_UART_TX / P0.19)
#define GPS_TX_PIN (0 + 21)      // MCU TX → GPS's RX (vendor GPS_UART_RX / P0.21)
#define PIN_GPS_RF_EN (0 + 29)   // GPS_RF_EN: P0.29 - RF front-end enable, not a reset line
#define GPS_RF_EN_ACTIVE HIGH

#define GPS_THREAD_INTERVAL 50

#define PIN_SERIAL1_RX GPS_RX_PIN
#define PIN_SERIAL1_TX GPS_TX_PIN

// SPI Interfaces (LoRa on SPI0)
#define SPI_INTERFACES_COUNT 2

// For LORA, SPI 0
#define PIN_SPI_MISO (0 + 17)
#define PIN_SPI_MOSI (0 + 15)
#define PIN_SPI_SCK (0 + 13)

// Battery
// The battery sense is hooked to PIN_A0 (P0.2) via a divider controlled by ADC_CTRL.
#define BATTERY_SENSE_RESOLUTION_BITS 12
#define BATTERY_SENSE_RESOLUTION 4096.0
#undef AREF_VOLTAGE
#define AREF_VOLTAGE 3.0
#define VBAT_AR_INTERNAL AR_INTERNAL_3_0
#define ADC_MULTIPLIER (2.0F)

// No charge IC on this board - use native USB state as a charging proxy.
#define NRF_APM

// No piezo on this board - sound goes via I2S speaker only.
#define HAS_I2S_SPEAKER_NRF52    // MAX98357 amp, driven by NRF52I2SOutput (not HAS_I2S/ESP8266Audio)
#define SPEAKER_EN (32 + 11)     // P1.11 - amp main enable
#define SPEAKER_EN_2 (0 + 3)     // P0.3  - secondary enable (vendor firmware toggles both)
#define SPEAKER_BCLK (0 + 16)    // P0.16 - I2S bit clock
#define SPEAKER_DATA (0 + 20)    // P0.20 - I2S data (SDOUT)
#define SPEAKER_WS_LRCK (0 + 22) // P0.22 - I2S word select / LRCK

// ───────────────────────────────────────────────────────────────────────────
// PDM microphone (ST MP34DT05).
// TODO to enable a mic path:
// Use Adafruit nRF52 core's built-in PDM.h wrapper (Arduino-compatible
// API exists on nRF52840). Clock on MIC_SCLK, data on MIC_DATA.
// ───────────────────────────────────────────────────────────────────────────
#define MIC_SCLK (32 + 3) // P1.3 - PDM clock (MIC_SCLK on vendor header)
#define MIC_DATA (32 + 5) // P1.5 - PDM data (MIC_DATA on vendor header)

#define SERIAL_PRINT_PORT 0

#ifdef __cplusplus
}
#endif

/*----------------------------------------------------------------------------
 *        Arduino objects - C++ only
 *----------------------------------------------------------------------------*/

#endif