feat: add Raspberry Pi Pico 2 + W5500 + E22-900M30S variant

cvaldess · claude · cvaldess · commit 39e9a7920e81 · 2026-04-17T07:44:37.000+02:00
Adds community variant for Raspberry Pi Pico 2 (RP2350, 4 MB flash)
with external WIZnet W5500 Ethernet module and EBYTE E22-900M30S LoRa
module (SX1262, 30 dBm PA, 868/915 MHz).

Key details:
- LoRa on SPI1: GP10/11/12/13 (SCK/MOSI/MISO/CS), RST=GP15,
  DIO1=GP14, BUSY=GP2, RXEN=GP3 (held HIGH via SX126X_ANT_SW)
- W5500 on SPI0: GP16/17/18/19/20 (MISO/CS/SCK/MOSI/RST)
- SX126X_DIO2_AS_RF_SWITCH: DIO2→TXEN bridge on module handles PA
- SX126X_DIO3_TCXO_VOLTAGE 1.8: TCXO support via EBYTE_E22 flags
- DHCP timeout reduced to 10 s to avoid blocking LoRa startup
- GPS on UART1/Serial2: GP8 TX, GP9 RX
- Reuses WIZNET_5500_EVB_PICO2 code paths for Ethernet init

Co-Authored-By: Claude Sonnet 4.6 &lt;noreply@anthropic.com&gt;
diff --git a/src/DebugConfiguration.h b/src/DebugConfiguration.h
@@ -147,7 +147,9 @@ extern "C" void logLegacy(const char *level, const char *fmt, ...);
 // Default Bluetooth PIN
 #define defaultBLEPin 123456
 
-#if HAS_ETHERNET && !defined(USE_WS5500)
+#if HAS_ETHERNET && defined(WIZNET_5500_EVB_PICO2)
+#include <Ethernet.h> // arduino-libraries/Ethernet — supports W5500 auto-detect
+#elif HAS_ETHERNET && !defined(USE_WS5500)
 #include <RAK13800_W5100S.h>
 #endif // HAS_ETHERNET
 
diff --git a/src/mesh/api/ethServerAPI.h b/src/mesh/api/ethServerAPI.h
@@ -1,8 +1,12 @@
 #pragma once
 
 #include "ServerAPI.h"
-#ifndef USE_WS5500
+#if !defined(USE_WS5500)
+#if defined(WIZNET_5500_EVB_PICO2)
+#include <Ethernet.h>
+#else
 #include <RAK13800_W5100S.h>
+#endif
 
 /**
  * Provides both debug printing and, if the client starts sending protobufs to us, switches to send/receive protobufs
diff --git a/src/mesh/eth/ethClient.cpp b/src/mesh/eth/ethClient.cpp
@@ -6,7 +6,11 @@
 #include "main.h"
 #include "mesh/api/ethServerAPI.h"
 #include "target_specific.h"
+#ifdef WIZNET_5500_EVB_PICO2
+#include <Ethernet.h> // arduino-libraries/Ethernet — supports W5100/W5200/W5500
+#else
 #include <RAK13800_W5100S.h>
+#endif
 #include <SPI.h>
 
 #if HAS_NETWORKING
@@ -69,13 +73,21 @@ static int32_t reconnectETH()
             delay(100);
 #endif
 
+#ifdef WIZNET_5500_EVB_PICO2 // Re-configure SPI0 for the on-board W5500
+            SPI.setRX(ETH_SPI0_MISO);
+            SPI.setSCK(ETH_SPI0_SCK);
+            SPI.setTX(ETH_SPI0_MOSI);
+            SPI.begin();
+            Ethernet.init(PIN_ETHERNET_SS);
+#else
 #ifdef RAK11310
             ETH_SPI_PORT.setSCK(PIN_SPI0_SCK);
             ETH_SPI_PORT.setTX(PIN_SPI0_MOSI);
             ETH_SPI_PORT.setRX(PIN_SPI0_MISO);
             ETH_SPI_PORT.begin();
 #endif
             Ethernet.init(ETH_SPI_PORT, PIN_ETHERNET_SS);
+#endif
 
             int status = 0;
             if (config.network.address_mode == meshtastic_Config_NetworkConfig_AddressMode_DHCP) {
@@ -182,13 +194,21 @@ bool initEthernet()
         digitalWrite(PIN_ETHERNET_RESET, HIGH); // Reset Time.
 #endif
 
+#ifdef WIZNET_5500_EVB_PICO2 // Configure SPI0 for the on-board W5500
+        SPI.setRX(ETH_SPI0_MISO);
+        SPI.setSCK(ETH_SPI0_SCK);
+        SPI.setTX(ETH_SPI0_MOSI);
+        SPI.begin();
+        Ethernet.init(PIN_ETHERNET_SS);
+#else
 #ifdef RAK11310 // Initialize the SPI port
         ETH_SPI_PORT.setSCK(PIN_SPI0_SCK);
         ETH_SPI_PORT.setTX(PIN_SPI0_MOSI);
         ETH_SPI_PORT.setRX(PIN_SPI0_MISO);
         ETH_SPI_PORT.begin();
 #endif
         Ethernet.init(ETH_SPI_PORT, PIN_ETHERNET_SS);
+#endif
 
         uint8_t mac[6];
 
@@ -201,7 +221,7 @@ bool initEthernet()
 
         if (config.network.address_mode == meshtastic_Config_NetworkConfig_AddressMode_DHCP) {
             LOG_INFO("Start Ethernet DHCP");
-            status = Ethernet.begin(mac);
+            status = Ethernet.begin(mac, 10000); // 10s timeout instead of default 60s
         } else if (config.network.address_mode == meshtastic_Config_NetworkConfig_AddressMode_STATIC) {
             LOG_INFO("Start Ethernet Static");
             Ethernet.begin(mac, config.network.ipv4_config.ip, config.network.ipv4_config.dns, config.network.ipv4_config.gateway,
diff --git a/src/platform/rp2xx0/architecture.h b/src/platform/rp2xx0/architecture.h
@@ -33,6 +33,8 @@
 #define HW_VENDOR meshtastic_HardwareModel_RP2040_LORA
 #elif defined(RP2040_FEATHER_RFM95)
 #define HW_VENDOR meshtastic_HardwareModel_RP2040_FEATHER_RFM95
+#elif defined(WIZNET_5500_EVB_PICO2)
+#define HW_VENDOR meshtastic_HardwareModel_PRIVATE_HW
 #elif defined(PRIVATE_HW)
 #define HW_VENDOR meshtastic_HardwareModel_PRIVATE_HW
 #endif
diff --git a/variants/rp2350/pico2_w5500_e22/README.md b/variants/rp2350/pico2_w5500_e22/README.md
@@ -0,0 +1,151 @@
+# Raspberry Pi Pico 2 + W5500 + E22-900M30S — Meshtastic Variant
+
+Meshtastic support for a **Raspberry Pi Pico 2** (RP2350, 4 MB flash) with an external **W5500** Ethernet module and an **EBYTE E22-900M30S** LoRa module.
+
+---
+
+## Required Hardware
+
+| Component | Model                         | Notes                                    |
+|-----------|-------------------------------|------------------------------------------|
+| MCU       | Raspberry Pi Pico 2           | RP2350 @ 150 MHz, 512 KB RAM, 4 MB flash |
+| Ethernet  | W5500 module                  | Any WIZnet W5500 breakout board          |
+| LoRa      | EBYTE E22-900M30S             | SX1262 + 30 dBm PA, 868/915 MHz         |
+
+---
+
+## Pinout
+
+### System pins (Pico 2, fixed)
+
+| GPIO | Function                                      |
+|------|-----------------------------------------------|
+| GP24 | VBUS sense — HIGH when USB is connected       |
+| GP25 | User LED (heartbeat)                          |
+| GP29 | ADC3 — VSYS/3, measures supply voltage        |
+
+### W5500 Ethernet (SPI0)
+
+| W5500 signal | Pico 2 GPIO |
+|--------------|-------------|
+| MISO         | GP16        |
+| CS / SCS     | GP17        |
+| SCK          | GP18        |
+| MOSI         | GP19        |
+| RST          | GP20        |
+| INT          | — (nc)      |
+| VCC          | 3.3V        |
+| GND          | GND         |
+
+> SPI0 is reserved for the W5500.
+
+### E22-900M30S LoRa (SPI1)
+
+| E22 signal | Pico 2 GPIO | Notes                                          |
+|------------|-------------|------------------------------------------------|
+| SCK        | GP10        | SPI1 clock                                     |
+| MOSI       | GP11        | SPI1 TX                                        |
+| MISO       | GP12        | SPI1 RX                                        |
+| NSS / CS   | GP13        | Chip select                                    |
+| RESET      | GP15        | Active LOW reset                               |
+| DIO1       | GP14        | IRQ interrupt                                  |
+| BUSY       | GP2         | Module busy indicator                          |
+| RXEN       | GP3         | LNA enable — held HIGH permanently            |
+| TXEN       | ← DIO2      | See wiring note below                          |
+| VCC        | 3.3V        | Add a 100 µF capacitor close to the module    |
+| GND        | GND         | —                                              |
+
+> See `wiring.svg` in this directory for the full connection diagram.
+
+---
+
+## Special wiring: DIO2 → TXEN bridge on the E22 module
+
+The E22-900M30S does **not** connect DIO2 to the TXEN pin of its PA internally. They must be bridged with a short wire or solder bridge **on the module itself**:
+
+```
+E22 DIO2 pin  ──┐
+                ├── wire / solder bridge on the module
+E22 TXEN pin  ──┘
+```
+
+With this bridge in place, `SX126X_DIO2_AS_RF_SWITCH` causes the SX1262 to drive DIO2 HIGH automatically during TX, enabling the PA without needing an RP2350 GPIO for TXEN.
+
+**Without this bridge the module will not transmit.**
+
+---
+
+## Build
+
+```bash
+pio run -e pico2_w5500_e22
+```
+
+### Flash — BOOTSEL mode
+
+1. Hold the **BOOTSEL** button on the Pico 2.
+2. Connect USB to the PC — it appears as a `RPI-RP2` storage drive.
+3. Copy the `.uf2` file:
+
+```
+.pio/build/pico2_w5500_e22/firmware-pico2_w5500_e22-*.uf2
+```
+
+Or directly with picotool:
+
+```bash
+pio run -e pico2_w5500_e22 -t upload
+```
+
+---
+
+## Network usage
+
+This board uses Ethernet (no Wi-Fi). From the Meshtastic app:
+
+- **Enable Ethernet** under `Config → Network → Ethernet Enabled`
+- **DHCP** by default; static IP can also be configured
+
+Services available once connected:
+
+| Service | Details                     |
+|---------|-----------------------------|
+| NTP     | Time synchronization        |
+| MQTT    | Messages to external broker |
+| API     | TCP socket on port 4403     |
+| Syslog  | Remote logging (optional)   |
+
+---
+
+## Technical notes
+
+### LoRa — RF control
+
+| Define                         | Effect                                                        |
+|--------------------------------|---------------------------------------------------------------|
+| `SX126X_ANT_SW 3`              | GP3 (RXEN) driven HIGH at init and never toggled again        |
+| `SX126X_DIO2_AS_RF_SWITCH`     | SX1262 drives DIO2 HIGH during TX → enables TXEN via bridge  |
+| `SX126X_DIO3_TCXO_VOLTAGE 1.8` | E22 TCXO controlled by DIO3                                  |
+| `-D EBYTE_E22`                 | Enables TCXO support in firmware                              |
+| `-D EBYTE_E22_900M30S`         | Sets `TX_GAIN_LORA=10`, max power 22 dBm                     |
+
+> RXEN and TXEN may both be HIGH simultaneously during TX — this is safe for the E22 RF switch.
+
+### Ethernet
+
+- Library: `arduino-libraries/Ethernet@^2.0.2` (supports W5100/W5200/W5500 auto-detection).
+- SPI0 is explicitly initialized with pins GP16/18/19 before `Ethernet.init()`.
+- DHCP timeout is set to 10 s (instead of the default 60 s) to avoid blocking LoRa startup.
+
+### HW_VENDOR
+
+Mapped to `meshtastic_HardwareModel_PRIVATE_HW` — no dedicated model exists in the Meshtastic protobuf for this hardware combination yet.
+
+---
+
+## Memory usage (reference build)
+
+| Resource | Used    | Total    | %     |
+|----------|---------|----------|-------|
+| RAM      | 94 KB   | 512 KB   | 18%   |
+| Flash    | 964 KB  | 3.58 MB  | 26.3% |
diff --git a/variants/rp2350/pico2_w5500_e22/platformio.ini b/variants/rp2350/pico2_w5500_e22/platformio.ini
@@ -0,0 +1,28 @@
+[env:pico2_w5500_e22]
+extends = rp2350_base
+board = rpipico2
+board_level = community
+upload_protocol = picotool
+
+build_flags =
+  ${rp2350_base.build_flags}
+  -ULED_BUILTIN                   # avoid "LED_BUILTIN redefined" warnings from framework common.h
+  -D WIZNET_5500_EVB_PICO2        # reuse same code paths as EVB variant
+  -I variants/rp2350/pico2_w5500_e22
+  -D DEBUG_RP2040_PORT=Serial
+  -D HW_SPI1_DEVICE
+  -D EBYTE_E22                    # activates TCXO support (SX126X_DIO3_TCXO_VOLTAGE)
+  -D EBYTE_E22_900M30S            # activates TX_GAIN_LORA=7 / SX126X_MAX_POWER=22
+
+# Re-enable Ethernet and API source paths excluded in rp2350_base
+build_src_filter = ${rp2350_base.build_src_filter} +<mesh/eth/> +<mesh/api/> +<mqtt/>
+
+lib_deps =
+  ${rp2350_base.lib_deps}
+  ${networking_base.lib_deps}
+  ${networking_extra.lib_deps}
+  # Standard WIZnet Ethernet library — supports W5100/W5200/W5500 auto-detect
+  arduino-libraries/Ethernet@^2.0.2
+
+debug_build_flags = ${rp2350_base.build_flags}, -g
+debug_tool = cmsis-dap
diff --git a/variants/rp2350/pico2_w5500_e22/variant.h b/variants/rp2350/pico2_w5500_e22/variant.h
@@ -0,0 +1,83 @@
+// Raspberry Pi Pico 2 + external W5500 Ethernet module + EBYTE E22-900M30S
+// RP2350 (4 MB flash) — wire modules to the GPIO pins listed below
+//
+// LoRa (SX1262 / E22-900M30S) on SPI1:
+//   SCK=GP10  MOSI=GP11  MISO=GP12  CS=GP13
+//   RST=GP15  DIO1/IRQ=GP14  BUSY=GP2  RXEN=GP3
+//   TXEN: bridge E22_DIO2 → E22_TXEN on the module (no RP2350 GPIO needed)
+//
+// W5500 Ethernet on SPI0:
+//   MISO=GP16  CS=GP17  SCK=GP18  MOSI=GP19  RST=GP20
+//
+// See wiring.svg in this directory for a complete connection diagram.
+
+#define ARDUINO_ARCH_AVR
+
+// Onboard LED (GP25 on Pico 2)
+#define LED_POWER PIN_LED
+
+// Power monitoring
+// GP24: VBUS sense – HIGH when USB is present (digital read)
+// GP29: ADC3 measures VSYS/3 (200 kΩ / 100 kΩ divider, same as standard Pico 2)
+#define EXT_PWR_DETECT 24
+#define BATTERY_PIN    29
+#define ADC_MULTIPLIER 3.0
+#define BATTERY_SENSE_RESOLUTION_BITS 12
+// No real battery — suppress false "battery at 100%" while USB powers VSYS
+#define NO_BATTERY_LEVEL_ON_CHARGE
+
+// Optional user button — connect a button between GP6 and GND
+// #define BUTTON_PIN 6
+// #define BUTTON_NEED_PULLUP
+
+// GPS on UART1 (Serial2) — GP8 TX, GP9 RX
+// GP8/GP9 belong to UART1, so we must use Serial2 (not the default Serial1/UART0).
+// GP0/GP1 (UART0 defaults) are free but the firmware treats pin 0 as "not configured".
+// GP4/GP5 occupied by I2C (SCL/SDA for BMP-280).
+#define HAS_GPS 1
+#define GPS_TX_PIN 8
+#define GPS_RX_PIN 9
+#define GPS_BAUDRATE 38400
+#define GPS_SERIAL_PORT Serial2
+
+// ---- EBYTE E22-900M30S on SPI1 -----------------------------------------
+#define USE_SX1262
+
+#undef LORA_SCK
+#undef LORA_MISO
+#undef LORA_MOSI
+#undef LORA_CS
+
+#define LORA_SCK  10
+#define LORA_MOSI 11
+#define LORA_MISO 12
+#define LORA_CS   13
+
+#define LORA_DIO0  RADIOLIB_NC
+#define LORA_RESET 15
+#define LORA_DIO1  14   // IRQ
+#define LORA_DIO2  2    // BUSY
+#define LORA_DIO3  RADIOLIB_NC
+
+#ifdef USE_SX1262
+#define SX126X_CS    LORA_CS
+#define SX126X_DIO1  LORA_DIO1
+#define SX126X_BUSY  LORA_DIO2
+#define SX126X_RESET LORA_RESET
+// GP3 = RXEN: driven HIGH at init and held there (LNA always enabled).
+// SX1262 drives DIO2 HIGH during TX → TXEN via bridge on E22 module.
+#define SX126X_ANT_SW 3
+#define SX126X_DIO2_AS_RF_SWITCH
+#define SX126X_DIO3_TCXO_VOLTAGE 1.8
+#endif
+
+// ---- W5500 Ethernet on SPI0 --------------------------------------------
+#define HAS_ETHERNET 1
+
+#define ETH_SPI0_MISO 16
+#define ETH_SPI0_SCK  18
+#define ETH_SPI0_MOSI 19
+
+#define PIN_ETHERNET_RESET 20
+#define PIN_ETHERNET_SS    17
+#define ETH_SPI_PORT       SPI
diff --git a/variants/rp2350/pico2_w5500_e22/wiring.svg b/variants/rp2350/pico2_w5500_e22/wiring.svg
