Add radio simulation

tutorials/nxp/frdm-mcxw71/minimal/Makefile

@@ -14,6 +14,7 @@ CFLAGS += -mcpu=cortex-m33 -mthumb -mfloat-abi=hard -mfpu=fpv5-sp-d16 $(CFLAGS_E
 LDFLAGS ?= -Tlink.ld -nostdlib -nostartfiles --specs=nano.specs -lc -lm -lgcc -Wl,--gc-sections
 
 SOURCES = main.c hal.c $(MGDIR)/mongoose.c
+
 SOURCES += $(MGDIR)/tutorials/mqtt/mqtt-client/mongoose_mqtt.c
 SOURCES += cmsis_mcxw71/MCXW/MCXW716C/gcc/startup_MCXW716C.S
 
@@ -23,9 +24,13 @@ firmware.bin: firmware.elf
 	arm-none-eabi-objcopy -O binary $< $@
 	arm-none-eabi-size --format=berkeley $<
 
-firmware.elf: cmsis_core cmsis_mcxw71 $(SOURCES) $(wildcard *.h) link.ld Makefile
+firmware.elf: cmsis_core cmsis_mcxw71 $(SOURCES) $(wildcard *.h) $(MGDIR)/mongoose.h link.ld Makefile mesh-config
 	arm-none-eabi-gcc $(SOURCES) $(CFLAGS) $(LDFLAGS) -o $@
 
+# Rebuild when overriding the board address or timing.
+.PHONY: mesh-config
+mesh-config:
+
 cmsis_core:
 	git clone -q -c advice.detachedHead=false --depth 1 -b 5.9.0 https://github.com/ARM-software/CMSIS_5 $@
 

tutorials/nxp/frdm-mcxw71/minimal/hal.c

@@ -9,7 +9,7 @@
 // 802.15.4 register setup. Then select the legacy 802.15.4 demodulator and
 // CCA from RX digital. See PhyHwInit() in NXP ieee_802_15_4 PHY sources,
 // PhyPacketProcessor.c
-bool hal_radio_init(void) {
+void hal_radio_init(void) {
   uint32_t stat = RFMC_RF2P4GHZ_STAT_RST_STAT_MASK |
                   RFMC_RF2P4GHZ_STAT_LP_ACK_STAT_MASK;
   size_t i, n = 1000000;
@@ -20,7 +20,10 @@ bool hal_radio_init(void) {
         RFMC_RF2P4GHZ_CTRL_RST_MASK);  // Release radio reset, no low power
   while ((RFMC->RF2P4GHZ_STAT & stat) != 0 ||
          (RFMC->XO_STAT & RFMC_XO_STAT_XTAL_RDY_MASK) == 0) {
-    if (--n == 0) return false;  // Radio did not wake up
+    if (--n == 0) {
+      MG_ERROR(("Radio init failed"));  // Radio did not wake up
+      return;
+    }
   }
   RADIO_CTRL->LL_CTRL = RADIO_CTRL_LL_CTRL_ACTIVE_LL_MASK;
   RFMC->RF2P4GHZ_CTRL |=
@@ -31,17 +34,17 @@ bool hal_radio_init(void) {
   XCVR_MISC->XCVR_CTRL &= ~XCVR_MISC_XCVR_CTRL_DEMOD_SEL_MASK;
   XCVR_MISC->XCVR_CTRL |= XCVR_MISC_XCVR_CTRL_DEMOD_SEL(2);
   XCVR_ZBDEMOD->CCA_LQI_SRC |= XCVR_ZBDEMOD_CCA_LQI_SRC_CCA1_FROM_RX_DIG(1);
-  return true;
 }
 
-// Random bytes for Mongoose, MG_ENABLE_CUSTOM_RANDOM. Entropy is radio noise:
-// receiver RSSI, sampled while the radio receives, mixed with SysTick by
-// SHA-256. Good enough for random addresses and nonces, not a certified TRNG
-bool mg_random(void *buf, size_t len) {
-  static uint32_t counter;
-  uint8_t digest[32], *p = (uint8_t *) buf;
+// Random 32 bits, for mg_random(). Entropy is radio noise: receiver RSSI,
+// sampled while the radio receives, mixed with SysTick by SHA-256. One hash
+// fills a pool of 8 words. Good enough for random addresses and nonces, not
+// a certified TRNG
+uint32_t hal_rng_read(void) {
+  static uint32_t counter, pool[8];
+  static size_t avail;
   size_t i, n;
-  while (len > 0) {
+  if (avail == 0) {
     mg_sha256_ctx ctx;
     mg_sha256_init(&ctx);
     counter++;
@@ -51,11 +54,10 @@ bool mg_random(void *buf, size_t len) {
       mg_sha256_update(&ctx, (uint8_t *) sample, sizeof(sample));
       for (n = 0; n < 50; n++) __NOP();  // Let the RSSI update
     }
-    mg_sha256_final(digest, &ctx);
-    n = len < sizeof(digest) ? len : sizeof(digest);
-    memcpy(p, digest, n), p += n, len -= n;
+    mg_sha256_final((uint8_t *) pool, &ctx);
+    avail = sizeof(pool) / sizeof(pool[0]);
   }
-  return true;
+  return pool[--avail];
 }
 
 // Added to minimise the bin size: avoid pulling printf and friends
@@ -81,6 +83,26 @@ uint64_t hal_get_tick(void) {
   return s_ticks;
 }
 
+uint64_t mg_micros(void);
+// SysTick runs at the core clock and reloads every millisecond. Sample
+// the tick counter and the sub-millisecond counter in one critical section.
+uint64_t mg_micros(void) {
+  uint32_t primask = __get_PRIMASK(), val, pending;
+  uint64_t ms;
+  __disable_irq();
+  ms = hal_get_tick();
+  pending = SCB->ICSR & SCB_ICSR_PENDSTSET_Msk;
+  val = SysTick->VAL;
+  if (pending != (SCB->ICSR & SCB_ICSR_PENDSTSET_Msk)) {
+    pending = SCB_ICSR_PENDSTSET_Msk;
+    val = SysTick->VAL;
+  }
+  __set_PRIMASK(primask);
+  if (pending != 0 && val != 0) ms++;
+  return ms * 1000 + ((uint64_t) (SysTick->LOAD - val) * 1000) /
+                         (SysTick->LOAD + 1);
+}
+
 uint32_t SystemCoreClock;
 
 // Called by the startup code before .data and .bss are initialised, so it

tutorials/nxp/frdm-mcxw71/minimal/hal.h

@@ -17,11 +17,14 @@ uint64_t hal_get_tick(void);
 bool hal_timer_expired(volatile uint64_t *t, uint64_t period, uint64_t now);
 size_t hal_ram_used(void);
 size_t hal_ram_free(void);
-bool hal_radio_init(void);  // Set up the 2.4 GHz transceiver for 802.15.4
+void hal_radio_init(void);  // Set up the 2.4 GHz transceiver for 802.15.4
+uint32_t hal_rng_read(void);  // Random 32 bits, radio noise. See hal.c
 extern uint32_t SystemCoreClock;  // CPU clock, Hz. Set by hal_clock_init()
 
-
 #define BIT(x) (1UL << (x))
+#define PIN(port, num) ((((port) - 'A') << 8) | (num))
+#define PINNO(pin) (pin & 255)
+#define PINPORT(pin) (pin >> 8)
 #define CLRSET(reg, clear, set) ((reg) = ((reg) & ~(clear)) | (set))
 #define SIRC_FREQUENCY 6000000UL  // Slow IRC (FRO6M), Hz
 
@@ -92,15 +95,53 @@ static inline void hal_periph_clock(volatile uint32_t *mrcc, uint32_t src) {
   __DSB();
 }
 
-// LPUART1 is wired to the MCU-Link debug probe USB serial port.
-// TX = PTC3, RX = PTC2, both pin mux alternative 3. See board.h, pin_mux.c
-static inline void hal_uart_init(LPUART_Type *uart, unsigned long baud) {
+// PORT, the pin multiplexer, of a pin. Ports A..C
+static inline PORT_Type *hal_pin_port(uint16_t pin) {
+  PORT_Type *ports[] = {PORTA, PORTB, PORTC};
+  return ports[PINPORT(pin)];
+}
+
+// GPIO of a pin. Ports A..C
+static inline GPIO_Type *hal_pin_gpio(uint16_t pin) {
+  GPIO_Type *gpios[] = {GPIOA, GPIOB, GPIOC};
+  return gpios[PINPORT(pin)];
+}
+
+// Route a pin to function mux: 1 GPIO, others see the datasheet pinout.
+// Clocks its PORT: MRCC_PORTA..C are consecutive
+static inline void hal_pin_mux(uint16_t pin, uint32_t mux) {
+  hal_periph_clock(&MRCC->MRCC_PORTA + PINPORT(pin), 0);
+  hal_pin_port(pin)->PCR[PINNO(pin)] = PORT_PCR_MUX(mux);
+}
+
+static inline void hal_gpio_output(uint16_t pin) {
+  hal_pin_mux(pin, 1);
+  hal_periph_clock(&MRCC->MRCC_GPIOA + PINPORT(pin), 0);  // Consecutive, too
+  hal_pin_gpio(pin)->PDDR |= BIT(PINNO(pin));
+}
+
+static inline void hal_gpio_write(uint16_t pin, bool val) {
+  if (val) {
+    hal_pin_gpio(pin)->PSOR = BIT(PINNO(pin));
+  } else {
+    hal_pin_gpio(pin)->PCOR = BIT(PINNO(pin));
+  }
+}
+
+static inline void hal_gpio_toggle(uint16_t pin) {
+  hal_pin_gpio(pin)->PTOR = BIT(PINNO(pin));
+}
+
+// LPUART1, on tx and rx pins, pin mux alternative 3. On FRDM-MCXW71 it is
+// wired to the MCU-Link debug probe USB serial port: TX PTC3, RX PTC2, see
+// board.h, pin_mux.c
+static inline void hal_uart_init(LPUART_Type *uart, uint16_t tx, uint16_t rx,
+                                 unsigned long baud) {
   uint32_t src = MRCC_SRC_FRO192M, freq = hal_firc_freq();
   uint32_t best_osr = 16, best_sbr = 1, best_err = UINT32_MAX, osr;
   if (freq == 0) src = MRCC_SRC_FRO6M, freq = SIRC_FREQUENCY;  // FIRC off
-  hal_periph_clock(&MRCC->MRCC_PORTC, 0);
-  PORTC->PCR[2] = PORT_PCR_MUX(3);  // RX
-  PORTC->PCR[3] = PORT_PCR_MUX(3);  // TX
+  hal_pin_mux(rx, 3);
+  hal_pin_mux(tx, 3);
   hal_periph_clock(&MRCC->MRCC_LPUART1, src);
   // Find the oversampling ratio (4..32) that gives the lowest baud rate error
   for (osr = 4; osr <= 32; osr++) {
@@ -141,6 +182,11 @@ static inline void hal_wdog_disable(void) {
   while ((WDOG0->CS & WDOG_CS_RCS_MASK) == 0) (void) 0;
 }
 
+// Random numbers come from radio noise, see hal_rng_read(): nothing to set
+// up here. The radio must be running, see hal_radio_init()
+static inline void hal_rng_init(void) {
+}
+
 static inline void hal_sys_init(void) {
   SCB->CPACR |= ((3UL << 10 * 2) | (3UL << 11 * 2));  // Enable FPU
   hal_wdog_disable();

tutorials/nxp/frdm-mcxw71/minimal/link.ld

@@ -33,6 +33,9 @@ SECTIONS {
     _ebss = .;
   } > sram
 
+  /* Health record, see MG_HEALTH_RAM: not cleared, survives a warm reset */
+  .mg_health (NOLOAD) : { KEEP(*(.mg_health .mg_health*)) } > sram
+
   . = ALIGN(8);
   _end = .;  /* Start of heap, see _sbrk() in hal.c */
 }

tutorials/nxp/frdm-mcxw71/minimal/main.c

@@ -1,24 +1,42 @@
 // Copyright (c) 2026 Cesanta Software Limited
 // All rights reserved
-//
-// IPv4 over IEEE 802.15.4 on FRDM-MCXW71, Mongoose built-in TCP/IP stack.
-// The radio carries Ethernet frames, channel 15, PAN ID 0xabcd. With the
-// FRDM-RW612 eth_radio_bridge tutorial, gets an address from the LAN's DHCP
-// server and is reachable from the LAN. Serves pages on ports 80 and 443
 
 #include "hal.h"
 #include "mongoose.h"
 
+#ifndef UART_DEBUG
 #define UART_DEBUG LPUART1  // MCU-Link USB serial port
+#define UART_DEBUG_TX_PIN PIN('C', 3)
+#define UART_DEBUG_RX_PIN PIN('C', 2)
+#endif
+
+#define LED1 PIN('A', 19)
+#define LED2 PIN('A', 20)
+#define LED3 PIN('A', 21)
 
 static void log_fn(char ch, void *param) {
   hal_uart_write_buf(param, &ch, 1);
 }
 
+static void blink_task(void) {
+  static uint64_t blink_timer = 0;
+  if (hal_timer_expired(&blink_timer, 500, hal_get_tick())) {
+    hal_gpio_toggle(LED2);
+  }
+}
+
 uint64_t mg_millis(void) {
   return hal_get_tick();
 }
 
+bool mg_random(void *buf, size_t len) {
+  for (size_t n = 0; n < len; n += sizeof(uint32_t)) {
+    uint32_t r = hal_rng_read();
+    memcpy((char *) buf + n, &r, n + sizeof(r) > len ? len - n : sizeof(r));
+  }
+  return true;
+}
+
 // Self-signed P-256 certificate and key for the HTTPS listener. Created by:
 //   openssl ecparam -genkey -name prime256v1 -noout -out key.pem
 //   openssl req -x509 -key key.pem -out cert.pem -days 3650 -subj /CN=mg
@@ -70,16 +88,21 @@ static void http_ev_handler(struct mg_connection *c, int ev, void *ev_data) {
 }
 
 int main(void) {
-  hal_clock_init();
-  hal_uart_init(UART_DEBUG, 115200);
-  mg_log_set_fn(log_fn, UART_DEBUG);
+  MG_HEALTH_INIT();
 
-  if (!hal_radio_init()) MG_ERROR(("Radio init failed"));
+  hal_clock_init();
+  hal_uart_init(UART_DEBUG, UART_DEBUG_TX_PIN, UART_DEBUG_RX_PIN, 115200);
+  mg_log_set_fn(log_fn, UART_DEBUG);
+  hal_rng_init();
+  hal_radio_init();
+  hal_gpio_output(LED1), hal_gpio_write(LED1, true);  // Active low
+  hal_gpio_output(LED2), hal_gpio_write(LED2, true);  // Active low
+  hal_gpio_output(LED3), hal_gpio_write(LED3, true);  // Active low
 
   struct mg_mgr mgr;
   mg_mgr_init(&mgr);
-  mg_http_listen(&mgr, "http://0.0.0.0:80", http_ev_handler, NULL);
-  mg_http_listen(&mgr, "https://0.0.0.0:443", http_ev_handler, NULL);
+  mg_http_listen(&mgr, "http://0.0.0.0", http_ev_handler, NULL);
+  mg_http_listen(&mgr, "https://0.0.0.0", http_ev_handler, NULL);
   mg_mqtt_init(&mgr);
 
   MG_INFO(("Initialised. CPU clock: %lu MHz", SystemCoreClock / 1000000));
@@ -89,6 +112,7 @@ int main(void) {
   for (;;) {
     mg_mgr_poll(&mgr, 0);
     mg_mqtt_poll(&mgr);
+    blink_task();
   }
 
   return 0;

tutorials/nxp/frdm-mcxw71/minimal/mongoose_config.h

@@ -1,9 +1,10 @@
 #pragma once
 #include "MCXW716C.h"
 
-// See https://mongoose.ws/docs/getting-started/build-environment/
+// See https://mongoose.ws/docs/getting-started/build-options/
 #define MG_ARCH MG_ARCH_ARMGCC
 #define MG_TLS MG_TLS_BUILTIN
+#define MQTT_CLIENT_ID "w71"  // For tutorials/mqtt/mqtt-client
 #define MG_OTA MG_OTA_MCXW71
 
 #define MG_ENABLE_TCPIP 1
@@ -21,3 +22,12 @@
     (mac)[0] = 2, (mac)[1] = b_[1], (mac)[2] = b_[2], (mac)[3] = b_[3]; \
     (mac)[4] = b_[4], (mac)[5] = b_[5];                                 \
   } while (0)
+
+// Crash report support. Health record lives in the .mg_health region, see link.ld
+#define MG_ENABLE_HEALTH 1
+#define MG_HEALTH_RAM __attribute__((section(".mg_health")))
+
+// mdash.net device management service support
+#define MG_ENABLE_MDASH 0
+#define MG_MDASH_KEY "..."  // Set this - mDash device token
+#define MG_FIRMWARE_VERSION "w71.1.0.0"

tutorials/nxp/frdm-rw612/bridge/Makefile

@@ -17,6 +17,7 @@ CFLAGS += -mcpu=cortex-m33+nodsp -mthumb -mfloat-abi=hard -mfpu=fpv5-sp-d16 $(CF
 LDFLAGS ?= -Tlink.ld -nostdlib -nostartfiles --specs=nano.specs -lc -lgcc -Wl,--gc-sections
 
 SOURCES = main.c hal.c radio.c startup.c flexspi.c flash_config.c $(MGDIR)/mongoose.c
+
 SOURCES += cmsis_rw612/devices/RW612/drivers/fsl_clock.c
 SOURCES += cmsis_rw612/devices/RW612/drivers/fsl_trng.c
 SOURCES += cmsis_rw612/devices/RW612/drivers/fsl_reset.c
@@ -35,9 +36,13 @@ firmware.bin: firmware.elf
 	arm-none-eabi-objcopy -O binary $< $@
 	arm-none-eabi-size --format=berkeley $<
 
-firmware.elf: cmsis_core cmsis_rw612 $(RADIO_FW) $(SOURCES) $(wildcard *.h) link.ld Makefile mongoose_config.h
+firmware.elf: cmsis_core cmsis_rw612 $(RADIO_FW) $(SOURCES) $(wildcard *.h) $(MGDIR)/mongoose.h link.ld Makefile mongoose_config.h mesh-config
 	arm-none-eabi-gcc $(SOURCES) $(CFLAGS) $(LDFLAGS) -o $@
 
+# Rebuild when overriding the board address or timing.
+.PHONY: mesh-config
+mesh-config:
+
 cmsis_core:
 	git clone -q -c advice.detachedHead=false --depth 1 -b 5.9.0 https://github.com/ARM-software/CMSIS_5 $@
 
@@ -56,7 +61,7 @@ show_symbols_sorted_by_size: firmware.bin
 	arm-none-eabi-readelf -sW firmware.elf | sed 1,3d | sed 's,^.*: ,,' | tr -s ' ' | cut -d ' ' -f 2,7 | sort -nk1 | grep -v '^0 '
 
 flash: firmware.bin
-	(echo 'loadfile firmware.elf'; echo 'reset'; echo 'exit';) | JLinkExe -device RW612 -if SWD -speed 4000 -autoconnect 1 -NoGui 1 -ExitOnError 1
+	(echo 'loadfile firmware.elf'; echo 'reset'; echo 'go'; echo 'exit';) | JLinkExe -device RW612 -if SWD -speed 4000 -autoconnect 1 -NoGui 1 -ExitOnError 1
 #	JRun --nogui --device RW612 --if SWD firmware.elf
 
 clean:

tutorials/nxp/frdm-rw612/bridge/hal.c

@@ -26,6 +26,26 @@ uint64_t hal_get_tick(void) {
   return s_ticks;
 };
 
+uint64_t mg_micros(void);
+// SysTick runs at the core clock and reloads every millisecond. Sample
+// the tick counter and the sub-millisecond counter in one critical section.
+uint64_t mg_micros(void) {
+  uint32_t primask = __get_PRIMASK(), val, pending;
+  uint64_t ms;
+  __disable_irq();
+  ms = hal_get_tick();
+  pending = SCB->ICSR & SCB_ICSR_PENDSTSET_Msk;
+  val = SysTick->VAL;
+  if (pending != (SCB->ICSR & SCB_ICSR_PENDSTSET_Msk)) {
+    pending = SCB_ICSR_PENDSTSET_Msk;
+    val = SysTick->VAL;
+  }
+  __set_PRIMASK(primask);
+  if (pending != 0 && val != 0) ms++;
+  return ms * 1000 + ((uint64_t) (SysTick->LOAD - val) * 1000) /
+                         (SysTick->LOAD + 1);
+}
+
 uint32_t SystemCoreClock = SYS_FREQUENCY;
 int hal_radio_err;      // Result of hal_radio_init()
 void SystemInit(void) {  // Called automatically by startup code

tutorials/nxp/frdm-rw612/bridge/hal.h

@@ -152,16 +152,22 @@ static inline void hal_gpio_toggle(uint16_t pin) {
 #define MG_HAL_SYSTICK MG_HAL_SYSTICK_NONE
 #endif
 
-static inline void hal_uart_init(USART_Type *uart, unsigned long baud) {
-  if (uart == USART0) {
+static inline void hal_uart_init(USART_Type *uart, unsigned long baud,
+                                 uint16_t tx_pin, uint16_t rx_pin) {
+  if (uart == USART0 && tx_pin == PIN(0, 3) &&
+      rx_pin == PIN(0, 2)) {
     IO_MUX_SetPinMux(IO_MUX_FC0_USART_DATA);
-  } else if (uart == USART1) {
+  } else if (uart == USART1 && tx_pin == PIN(0, 8) &&
+      rx_pin == PIN(0, 9)) {
     IO_MUX_SetPinMux(IO_MUX_FC1_USART_DATA);
-  } else if (uart == USART2) {
+  } else if (uart == USART2 && tx_pin == PIN(0, 14) &&
+      rx_pin == PIN(0, 13)) {
     IO_MUX_SetPinMux(IO_MUX_FC2_USART_DATA);
-  } else if (uart == USART3) {
+  } else if (uart == USART3 && tx_pin == PIN(0, 26) &&
+      rx_pin == PIN(0, 24)) {
     IO_MUX_SetPinMux(IO_MUX_FC3_USART_DATA);
-  } else if (uart == USART14) {
+  } else if (uart == USART14 && tx_pin == PIN(1, 24) &&
+      rx_pin == PIN(1, 25)) {
     IO_MUX_SetPinMux(IO_MUX_FC14_USART_DATA);
   } else {
     return;

tutorials/nxp/frdm-rw612/bridge/main.c

@@ -0,0 +1,123 @@
+// Copyright (c) 2026 Cesanta Software Limited
+// All rights reserved
+
+#include "hal.h"
+#include "mongoose.h"
+
+#define LED_RADIO PIN(0, 12)  // Green, active low
+#define LED_LAN PIN(0, 0)     // Blue, active low
+#define LED_RED PIN(0, 1)     // Red, active low
+
+static uint64_t s_radio_led_until;
+
+// Cumulative totals. Up: radio -> LAN; down: LAN -> radio queue.
+static uint64_t s_frames_up, s_frames_down, s_bytes_up, s_bytes_down;
+static uint64_t s_radio_sent, s_radio_received;
+static size_t (*s_radio_tx)(struct mg_tcpip_if *, const void *, size_t);
+
+static size_t radio_tx(struct mg_tcpip_if *ifp, const void *buf, size_t len) {
+  size_t sent = s_radio_tx(ifp, buf, len);
+  if (sent != 0) s_radio_sent++;
+  return sent;
+}
+
+static size_t eth_up(const void *buf, size_t len, struct mg_tcpip_if *ifp) {
+  size_t sent = mg_tcpip_driver_rw612.tx(buf, len, ifp);
+  if (sent != 0) s_frames_up++, s_bytes_up += sent;
+  return sent;
+}
+
+static size_t eth_down(struct mg_mesh_node *node, const void *buf, size_t len) {
+  size_t queued = mg_mesh_default.tx(node, buf, len);
+  if (queued != 0) s_frames_down++, s_bytes_down += queued;
+  return queued;
+}
+
+static void radio_rx(struct mg_mesh_node *node, void *buf, size_t len) {
+  s_radio_received++;
+  s_radio_led_until = mg_millis() + 2;
+  mg_mesh_default.rx(node, buf, len);
+}
+
+static void log_fn(char ch, void *arg) {
+  hal_uart_write_buf(arg, &ch, 1);
+}
+
+uint64_t mg_millis(void) {
+  return hal_get_tick();
+}
+
+int main(void) {
+  static struct mg_tcpip_driver_rw612_data eth_data;
+  static struct mg_tcpip_if eth;
+  static struct mg_tcpip_driver eth_driver;
+  static char eth_queue[8192];
+  static struct mg_tcpip_driver_rw612w_data radio_data;
+  static struct mg_tcpip_if radio;
+  static struct mg_mesh mesh;
+  uint32_t lan_received = 0;
+  uint64_t lan_led_until = 0;
+  uint64_t link_timer = 0, stats_timer = 0;
+
+  hal_clock_init();
+  hal_rng_init();
+  hal_gpio_output(LED_RADIO);
+  hal_gpio_output(LED_LAN);
+  hal_gpio_output(LED_RED);
+  hal_gpio_write(LED_RADIO, true);
+  hal_gpio_write(LED_LAN, true);
+  hal_gpio_write(LED_RED, true);
+  hal_uart_init(USART3, 115200, PIN(0, 26), PIN(0, 24));
+  mg_log_set_fn(log_fn, USART3);
+  hal_ethernet_init();
+
+  mesh = mg_mesh_default;
+  mesh.tx = eth_down;
+  mesh.rx = radio_rx;  // Observe radio reception without modifying the driver.
+  radio_data.strategy = &mesh;
+  radio.driver = &mg_tcpip_driver_rw612w;
+  radio.driver_data = &radio_data;
+  if (!radio.driver->init(&radio)) return 1;
+  s_radio_tx = radio_data.mesh->tx;
+  radio_data.mesh->tx = radio_tx;
+
+  eth_data.mdc_cr = MG_DRIVER_MDC_CR;
+  eth_data.mdc_holdtime = MG_DRIVER_MDC_HOLDTIME;
+  eth_data.phy_addr = MG_TCPIP_PHY_ADDR;
+  eth_driver = mg_tcpip_driver_rw612;
+  eth_driver.tx = eth_up;
+  eth.driver = &eth_driver;
+  eth.driver_data = &eth_data;
+  memcpy(eth.mac, radio.mac, 6);
+  mg_queue_init(&eth.recv_queue, eth_queue, sizeof(eth_queue));
+  if (!eth.driver->init(&eth)) return 1;
+
+  ENET->RCR |= ENET_RCR_PROM_MASK;  // Receive frames addressed to radio nodes.
+  radio_data.mesh->lan = ð
+  radio_data.mesh->next_tick = 0;
+
+  MG_INFO(("Ethernet/radio bridge, channel %u", MG_802154_CHANNEL));
+  stats_timer = mg_millis() + 5000;
+  for (;;) {
+    uint64_t now = mg_millis();
+    if (mg_timer_expired(&link_timer, 100, mg_millis())) {
+      eth.state = eth.driver->poll(&eth, true) ? MG_TCPIP_STATE_UP
+                                               : MG_TCPIP_STATE_DOWN;
+    }
+    radio.driver->poll(&radio, false);
+    if (mg_timer_expired(&stats_timer, 5000, now)) {
+      MG_INFO(
+          ("ETH frames up/down %llu/%llu, bytes up/down "
+           "%llu/%llu, radio frames sent/rcvd %llu/%llu",
+           s_frames_up, s_frames_down, s_bytes_up, s_bytes_down, s_radio_sent,
+           s_radio_received));
+    }
+    if (eth.nrecv != lan_received) {
+      lan_received = eth.nrecv;
+      lan_led_until = now + 2;
+    }
+    hal_gpio_write(LED_RADIO, now >= s_radio_led_until);
+    hal_gpio_write(LED_LAN, now >= lan_led_until);
+  }
+  return 0;
+}

tutorials/nxp/frdm-rw612/bridge/mongoose_config.h

@@ -0,0 +1,13 @@
+#pragma once
+
+// See https://mongoose.ws/docs/getting-started/build-environment/
+#define MG_ARCH MG_ARCH_ARMGCC
+
+#define MG_ENABLE_TCPIP 1
+#define MG_ENABLE_DRIVER_RW612 1        // Ethernet
+#define MG_ENABLE_DRIVER_RW612W 1 // Mesh bridge over raw 802.15.4
+#define MG_ENABLE_CUSTOM_MILLIS 1
+
+
+// The bridge initializes and polls its two L2 interfaces directly.
+#define MG_ENABLE_TCPIP_DRIVER_INIT 0

tutorials/nxp/frdm-rw612/eth_radio_bridge/main.c

@@ -1,101 +0,0 @@
-// Copyright (c) 2026 Cesanta Software Limited
-// All rights reserved
-//
-// Ethernet <-> IEEE 802.15.4 radio bridge. Radio frames carry Ethernet frames
-// split into pieces, see mg_l2_802154_tx(). Radio nodes, e.g. the
-// FRDM-MCXW71 minimal tutorial, are on the Ethernet LAN: they get IPv4
-// addresses from its DHCP server. The bridge itself has no IP address.
-// Everything from the radio goes to Ethernet. From Ethernet, only broadcasts
-// and frames to radio nodes go to the radio, it is much slower
-
-#include "hal.h"
-#include "mongoose.h"
-
-#define UART_DEBUG USART3
-
-static void log_fn(char ch, void *param) {
-  hal_uart_write_buf(param, &ch, 1);
-}
-
-uint64_t mg_millis(void) {
-  return hal_get_tick();
-}
-
-// MAC addresses of radio nodes, learned from frames they send
-static uint8_t s_nodes[8][6];
-static size_t s_next;
-
-// Remember a radio node's MAC address, if new
-static void learn(const uint8_t *mac) {
-  size_t i, n = sizeof(s_nodes) / sizeof(s_nodes[0]);
-  for (i = 0; i < n && memcmp(s_nodes[i], mac, 6) != 0; i++) (void) 0;
-  if (i < n) return;
-  memcpy(s_nodes[s_next], mac, 6);
-  s_next = (s_next + 1) % n;
-  MG_INFO(("Radio node %M", mg_print_mac, mac));
-}
-
-// Is an Ethernet frame for the radio: broadcast, or to a radio node
-static bool for_radio(const uint8_t *dst) {
-  size_t i, n = sizeof(s_nodes) / sizeof(s_nodes[0]);
-  if (memcmp(dst, "\xff\xff\xff\xff\xff\xff", 6) == 0) return true;
-  for (i = 0; i < n && memcmp(s_nodes[i], dst, 6) != 0; i++) (void) 0;
-  return i < n;
-}
-
-int main(void) {
-  static struct mg_tcpip_driver_rw612_data eth_data = {
-      .mdc_cr = MG_DRIVER_MDC_CR, .phy_addr = MG_TCPIP_PHY_ADDR};
-  static struct mg_l2_802154_data radio_data = {
-      .channel = MG_L2_802154_CHANNEL, .pan_id = MG_L2_802154_PAN_ID};
-  static struct mg_tcpip_if eth = {.driver = &mg_tcpip_driver_rw612,
-                                   .driver_data = &eth_data};
-  static struct mg_tcpip_if radio = {.driver = &mg_tcpip_driver_rw612_154,
-                                     .driver_data = &radio_data};
-  static char eth_queue[8192];  // Filled by the Ethernet IRQ handler
-  static uint8_t frame[1540];
-  uint8_t uid[FSL_OCOTP_UID_LENGTH], digest[32];
-  uint32_t uid_len = sizeof(uid);
-  uint64_t timer = 0;
-  char *p;
-  size_t n;
-
-  hal_clock_init();
-  hal_uart_init(UART_DEBUG, 115200);
-  mg_log_set_fn(log_fn, UART_DEBUG);
-  if (hal_radio_err) {
-    MG_ERROR(("Radio firmware failed to start, step %d", hal_radio_err));
-  }
-
-  // MAC addresses made from the chip unique ID
-  memset(uid, 0, sizeof(uid));
-  OCOTP_ReadUniqueID(uid, &uid_len);
-  mg_sha256(digest, uid, sizeof(uid));
-  memcpy(eth.mac, digest, 6);
-  memcpy(radio.mac, digest + 6, 6);
-  eth.mac[0] = radio.mac[0] = 0x02;  // Locally administered, unicast
-
-  hal_ethernet_init();
-  mg_queue_init(&eth.recv_queue, eth_queue, sizeof(eth_queue));
-  if (!eth.driver->init(&eth)) MG_ERROR(("Ethernet init failed"));
-  if (!radio.driver->init(&radio)) MG_ERROR(("Radio init failed"));
-  ENET->RCR |= ENET_RCR_PROM_MASK;  // Receive frames for radio nodes, too
-  MG_INFO(("Bridge started, radio channel %d", radio_data.channel));
-
-  for (;;) {
-    if ((n = mg_queue_next(&eth.recv_queue, &p)) > 0) {  // Ethernet -> radio
-      if (n >= 14 && for_radio((uint8_t *) p)) radio.driver->tx(p, n, &radio);
-      mg_queue_del(&eth.recv_queue, n);
-    }
-    if ((n = radio.driver->rx(frame, sizeof(frame), &radio)) >= 14) {
-      learn(frame + 6);  // Radio -> Ethernet
-      eth.driver->tx(frame, n, &eth);
-    }
-    if (mg_timer_expired(&timer, 1000, mg_millis())) {  // Ethernet link
-      bool up = eth.driver->poll(&eth, true);
-      eth.state = up ? MG_TCPIP_STATE_UP : MG_TCPIP_STATE_DOWN;
-    }
-  }
-
-  return 0;
-}

tutorials/nxp/frdm-rw612/eth_radio_bridge/mongoose_config.h

@@ -1,10 +0,0 @@
-#pragma once
-
-// See https://mongoose.ws/docs/getting-started/build-environment/
-#define MG_ARCH MG_ARCH_ARMGCC
-
-#define MG_ENABLE_TCPIP 1
-#define MG_ENABLE_DRIVER_RW612 1       // Ethernet
-#define MG_ENABLE_DRIVER_RW612_154 1   // 802.15.4 radio
-#define MG_ENABLE_TCPIP_DRIVER_INIT 0  // main.c drives both, no TCP/IP stack
-#define MG_ENABLE_CUSTOM_MILLIS 1

tutorials/nxp/frdm-rw612/minimal/hal.h

@@ -147,16 +147,22 @@ static inline void hal_gpio_toggle(uint16_t pin) {
 #define MG_HAL_SYSTICK MG_HAL_SYSTICK_NONE
 #endif
 
-static inline void hal_uart_init(USART_Type *uart, unsigned long baud) {
-  if (uart == USART0) {
+static inline void hal_uart_init(USART_Type *uart, unsigned long baud,
+                                 uint16_t tx_pin, uint16_t rx_pin) {
+  if (uart == USART0 && tx_pin == PIN(0, 3) &&
+      rx_pin == PIN(0, 2)) {
     IO_MUX_SetPinMux(IO_MUX_FC0_USART_DATA);
-  } else if (uart == USART1) {
+  } else if (uart == USART1 && tx_pin == PIN(0, 8) &&
+      rx_pin == PIN(0, 9)) {
     IO_MUX_SetPinMux(IO_MUX_FC1_USART_DATA);
-  } else if (uart == USART2) {
+  } else if (uart == USART2 && tx_pin == PIN(0, 14) &&
+      rx_pin == PIN(0, 13)) {
     IO_MUX_SetPinMux(IO_MUX_FC2_USART_DATA);
-  } else if (uart == USART3) {
+  } else if (uart == USART3 && tx_pin == PIN(0, 26) &&
+      rx_pin == PIN(0, 24)) {
     IO_MUX_SetPinMux(IO_MUX_FC3_USART_DATA);
-  } else if (uart == USART14) {
+  } else if (uart == USART14 && tx_pin == PIN(1, 24) &&
+      rx_pin == PIN(1, 25)) {
     IO_MUX_SetPinMux(IO_MUX_FC14_USART_DATA);
   } else {
     return;

tutorials/nxp/frdm-rw612/minimal/main.c

@@ -96,7 +96,7 @@ int main(void) {
   hal_gpio_write(LED2, true);
   hal_gpio_output(LED3);
   hal_gpio_write(LED3, true);
-  hal_uart_init(UART_DEBUG, 115200);
+  hal_uart_init(UART_DEBUG, 115200, PIN(0, 26), PIN(0, 24));
   mg_log_set_fn(log_fn, UART_DEBUG);
 
   hal_ethernet_init();