diff --git a/Marlin/src/HAL/RP2040/HAL.cpp b/Marlin/src/HAL/RP2040/HAL.cpp
index e8d0eea7cd..9341480078 100644
--- a/Marlin/src/HAL/RP2040/HAL.cpp
+++ b/Marlin/src/HAL/RP2040/HAL.cpp
@@ -32,17 +32,123 @@
 extern "C" {
   #include "pico/bootrom.h"
   #include "hardware/watchdog.h"
+  #include "pico/multicore.h"
+  #include "hardware/adc.h"
+  #include "pico/time.h"
 }
 
 #if HAS_SD_HOST_DRIVE
   #include "msc_sd.h"
-  #include "usbd_cdc_if.h"
 #endif
 
+// Core 1 watchdog configuration
+#define CORE1_MAX_RESETS 5  // Maximum number of Core 1 resets before halting system
+
 // ------------------------
 // Public Variables
 // ------------------------
 
+volatile uint32_t adc_accumulators[5] = {0}; // Accumulators for oversampling (sum of readings)
+volatile uint8_t adc_counts[5] = {0};        // Count of readings accumulated per channel
+volatile uint16_t adc_values[5] = {512, 512, 512, 512, 512}; // Final oversampled ADC values (averages) - initialized to mid-range
+
+// Core 1 watchdog monitoring
+volatile uint32_t core1_last_heartbeat = 0; // Timestamp of Core 1's last activity
+volatile bool core1_watchdog_triggered = false; // Flag to indicate Core 1 reset
+volatile uint8_t core1_reset_count = 0; // Count of Core 1 resets - halt system if >= CORE1_MAX_RESETS
+volatile uint8_t current_pin;
+volatile bool MarlinHAL::adc_has_result;
+volatile uint8_t adc_channels_enabled[5] = {false}; // Track which ADC channels are enabled
+
+// Helper function for LED blinking patterns
+void blink_led_pattern(uint8_t blink_count, uint32_t blink_duration_us = 100000) {
+  #if DISABLED(PINS_DEBUGGING) && PIN_EXISTS(LED)
+    for (uint8_t i = 0; i < blink_count; i++) {
+      WRITE(LED_PIN, HIGH);
+      busy_wait_us(blink_duration_us);
+      WRITE(LED_PIN, LOW);
+      if (i < blink_count - 1) { // Don't delay after the last blink
+        busy_wait_us(blink_duration_us);
+      }
+    }
+  #endif
+}
+
+// Core 1 ADC reading task - dynamically reads all enabled channels with oversampling
+void core1_adc_task() {
+  static uint32_t last_led_toggle = 0;
+  const uint8_t OVERSAMPLENR = 16; // Standard Marlin oversampling count
+
+  // Signal successful Core 1 startup/restart
+  SERIAL_ECHO_MSG("Core 1 ADC task started");
+
+  while (true) {
+    // Update heartbeat timestamp at start of each scan cycle
+    core1_last_heartbeat = time_us_32();
+
+    // Scan all enabled ADC channels
+    for (uint8_t channel = 0; channel < 5; channel++) {
+      if (!adc_channels_enabled[channel]) continue;
+
+      // Enable temperature sensor if reading channel 4
+      if (channel == 4) {
+        adc_set_temp_sensor_enabled(true);
+      }
+
+      // Select and read the channel
+      adc_select_input(channel);
+      busy_wait_us(100); // Settling delay
+      adc_fifo_drain();
+      adc_run(true);
+
+      // Wait for conversion with timeout
+      uint32_t timeout = 10000;
+      while (adc_fifo_is_empty() && timeout--) {
+        busy_wait_us(1);
+      }
+
+      adc_run(false);
+      uint16_t reading = adc_fifo_is_empty() ? 0 : adc_fifo_get();
+
+      // Accumulate readings for oversampling
+      adc_accumulators[channel] += reading;
+      adc_counts[channel]++;
+
+      // Update the averaged value with current accumulation (provides immediate valid data)
+      adc_values[channel] = adc_accumulators[channel] / adc_counts[channel];
+
+      // When we reach the full oversampling count, reset accumulator for next cycle
+      if (adc_counts[channel] >= OVERSAMPLENR) {
+        adc_accumulators[channel] = 0;
+        adc_counts[channel] = 0;
+      }
+
+      // Disable temp sensor after reading to save power
+      if (channel == 4) {
+        adc_set_temp_sensor_enabled(false);
+      }
+    }
+
+    // Core 1 LED indicator: Double blink every 2 seconds to show Core 1 is active
+    uint32_t now = time_us_32();
+    if (now - last_led_toggle >= 2000000) { // 2 seconds
+      last_led_toggle = now;
+      #if DISABLED(PINS_DEBUGGING) && PIN_EXISTS(LED)
+        // Triple blink pattern if watchdog was triggered (shows Core 1 was reset)
+        if (core1_watchdog_triggered) {
+          core1_watchdog_triggered = false; // Clear flag
+          blink_led_pattern(3); // Triple blink for watchdog reset
+        } else {
+          blink_led_pattern(2); // Normal double blink
+        }
+      #endif
+    }
+
+    // Delay between full scan cycles
+    busy_wait_us(10000); // 10ms between scans
+  }
+}
+
 volatile uint16_t adc_result;
 
 // ------------------------
@@ -118,9 +224,28 @@ void MarlinHAL::reboot() { watchdog_reboot(0, 0, 1); }
   }
 
   void MarlinHAL::watchdog_refresh() {
+    // If Core 1 has reset CORE1_MAX_RESETS+ times, stop updating watchdog to halt system
+    if (core1_reset_count >= CORE1_MAX_RESETS) {
+      SERIAL_ECHO_MSG("Core 1 reset limit exceeded (", core1_reset_count, " resets) - halting system for safety");
+      return; // Don't update watchdog - system will halt
+    }
+
     watchdog_update();
+
+    // Check Core 1 watchdog (15 second timeout)
+    uint32_t now = time_us_32();
+    if (now - core1_last_heartbeat > 15000000) { // 15 seconds
+      // Core 1 appears stuck - reset it
+      multicore_reset_core1();
+      multicore_launch_core1(core1_adc_task);
+      core1_watchdog_triggered = true; // Signal for LED indicator
+      core1_reset_count++; // Increment reset counter
+      SERIAL_ECHO_MSG("Core 1 ADC watchdog triggered - resetting Core 1 (attempt ", core1_reset_count, ")");
+    }
+
     #if DISABLED(PINS_DEBUGGING) && PIN_EXISTS(LED)
-      TOGGLE(LED_PIN);  // heartbeat indicator
+      // Core 0 LED indicator: Single toggle every watchdog refresh (shows Core 0 activity)
+      TOGGLE(LED_PIN);
     #endif
   }
 
@@ -130,43 +255,35 @@ void MarlinHAL::reboot() { watchdog_reboot(0, 0, 1); }
 // ADC
 // ------------------------
 
-volatile bool MarlinHAL::adc_has_result = false;
-
 void MarlinHAL::adc_init() {
   analogReadResolution(HAL_ADC_RESOLUTION);
   ::adc_init();
   adc_fifo_setup(true, false, 1, false, false);
-  irq_set_exclusive_handler(ADC_IRQ_FIFO, adc_exclusive_handler);
-  irq_set_enabled(ADC_IRQ_FIFO, true);
-  adc_irq_set_enabled(true);
+  // Launch Core 1 for continuous ADC reading
+  multicore_launch_core1(core1_adc_task);
+  adc_has_result = true; // Results are always available with continuous sampling
 }
 
 void MarlinHAL::adc_enable(const pin_t pin) {
-  if (pin >= A0 && pin <= A3)
+  if (pin >= A0 && pin <= A3) {
     adc_gpio_init(pin);
-  else if (pin == HAL_ADC_MCU_TEMP_DUMMY_PIN)
-    adc_set_temp_sensor_enabled(true);
-}
-
-void MarlinHAL::adc_start(const pin_t pin) {
-  adc_has_result = false;
-  // Select an ADC input. 0...3 are GPIOs 26...29 respectively.
-  adc_select_input(pin == HAL_ADC_MCU_TEMP_DUMMY_PIN ? 4 : pin - A0);
-  adc_run(true);
-}
-
-void MarlinHAL::adc_exclusive_handler() {
-  adc_run(false); // Disable since we only want one result
-  irq_clear(ADC_IRQ_FIFO); // Clear the IRQ
-
-  if (adc_fifo_get_level() >= 1) {
-    adc_result = adc_fifo_get(); // Pop the result
-    adc_fifo_drain();
-    adc_has_result = true; // Signal the end of the conversion
+    adc_channels_enabled[pin - A0] = true; // Mark this channel as enabled
+  }
+  else if (pin == HAL_ADC_MCU_TEMP_DUMMY_PIN) {
+    adc_channels_enabled[4] = true; // Mark MCU temp channel as enabled
   }
 }
 
-uint16_t MarlinHAL::adc_value() { return adc_result; }
+void MarlinHAL::adc_start(const pin_t pin) {
+  // Just store which pin we need to read - values are continuously updated by Core 1
+  current_pin = pin;
+}
+
+uint16_t MarlinHAL::adc_value() {
+  // Return the latest ADC value from Core 1's continuous readings
+  const uint8_t channel = (current_pin == HAL_ADC_MCU_TEMP_DUMMY_PIN) ? 4 : (current_pin - A0);
+  return adc_values[channel];
+}
 
 // Reset the system to initiate a firmware flash
 void flashFirmware(const int16_t) { hal.reboot(); }
diff --git a/Marlin/src/HAL/RP2040/HAL.h b/Marlin/src/HAL/RP2040/HAL.h
index 11472f72f5..206847053b 100644
--- a/Marlin/src/HAL/RP2040/HAL.h
+++ b/Marlin/src/HAL/RP2040/HAL.h
@@ -40,6 +40,11 @@
   #include "msc_sd.h"
 #endif
 
+// ADC index 4 is the MCU temperature
+#define HAL_ADC_MCU_TEMP_DUMMY_PIN 127
+#define TEMP_SOC_PIN HAL_ADC_MCU_TEMP_DUMMY_PIN   // ADC4 is internal temp sensor
+#include "temp_soc.h"
+
 //
 // Serial Ports
 //
@@ -85,8 +90,6 @@ typedef libServo hal_servo_t;
 #else
   #define HAL_ADC_RESOLUTION 12
 #endif
-// ADC index 4 is the MCU temperature
-#define HAL_ADC_MCU_TEMP_DUMMY_PIN 127
 
 //
 // Pin Mapping for M42, M43, M226
@@ -164,9 +167,6 @@ public:
   // Begin ADC sampling on the given pin. Called from Temperature::isr!
   static void adc_start(const pin_t pin);
 
-  // This ADC runs a periodic task
-  static void adc_exclusive_handler();
-
   // Is the ADC ready for reading?
   static volatile bool adc_has_result;
   static bool adc_ready() { return adc_has_result; }
diff --git a/Marlin/src/HAL/RP2040/eeprom/eeprom_flash.cpp b/Marlin/src/HAL/RP2040/eeprom/eeprom_flash.cpp
index 89e882d77b..bf52109173 100644
--- a/Marlin/src/HAL/RP2040/eeprom/eeprom_flash.cpp
+++ b/Marlin/src/HAL/RP2040/eeprom/eeprom_flash.cpp
@@ -31,28 +31,48 @@
 
 // NOTE: The Bigtreetech SKR Pico has an onboard W25Q16 flash module
 
-// Use EEPROM.h for compatibility, for now.
-#include <EEPROM.h>
+// RP2040 Flash-based EEPROM emulation using internal flash memory
+#include <hardware/flash.h>
+#include <hardware/sync.h>
 
-static bool eeprom_data_written = false;
+// Flash sector size is already defined in hardware/flash.h as FLASH_SECTOR_SIZE
+// Place EEPROM emulation at the end of flash, before the filesystem
+// This assumes 2MB flash, adjust if using different flash size
+#define FLASH_TARGET_OFFSET (PICO_FLASH_SIZE_BYTES - FLASH_SECTOR_SIZE)
 
 #ifndef MARLIN_EEPROM_SIZE
   #define MARLIN_EEPROM_SIZE size_t(E2END + 1)
 #endif
+
+static uint8_t eeprom_buffer[MARLIN_EEPROM_SIZE];
+static bool eeprom_data_written = false;
+static bool eeprom_initialized = false;
 size_t PersistentStore::capacity() { return MARLIN_EEPROM_SIZE; }
 
 bool PersistentStore::access_start() {
-  EEPROM.begin(); // Avoid EEPROM.h warning (do nothing)
-  eeprom_buffer_fill();
+  if (!eeprom_initialized) {
+    // Read from flash into buffer
+    const uint8_t *flash_data = (const uint8_t *)(XIP_BASE + FLASH_TARGET_OFFSET);
+    memcpy(eeprom_buffer, flash_data, MARLIN_EEPROM_SIZE);
+    eeprom_initialized = true;
+  }
   return true;
 }
 
 bool PersistentStore::access_finish() {
   if (eeprom_data_written) {
     TERN_(HAS_PAUSE_SERVO_OUTPUT, PAUSE_SERVO_OUTPUT());
-    hal.isr_off();
-    eeprom_buffer_flush();
-    hal.isr_on();
+
+    // Disable interrupts during flash write
+    const uint32_t intstate = save_and_disable_interrupts();
+
+    // Erase and program the sector
+    flash_range_erase(FLASH_TARGET_OFFSET, FLASH_SECTOR_SIZE);
+    flash_range_program(FLASH_TARGET_OFFSET, eeprom_buffer, MARLIN_EEPROM_SIZE);
+
+    // Restore interrupts
+    restore_interrupts(intstate);
+
     TERN_(HAS_PAUSE_SERVO_OUTPUT, RESUME_SERVO_OUTPUT());
     eeprom_data_written = false;
   }
@@ -62,8 +82,8 @@ bool PersistentStore::access_finish() {
 bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
   while (size--) {
     uint8_t v = *value;
-    if (v != eeprom_buffered_read_byte(pos)) {
-      eeprom_buffered_write_byte(pos, v);
+    if (pos < (int)MARLIN_EEPROM_SIZE && v != eeprom_buffer[pos]) {
+      eeprom_buffer[pos] = v;
       eeprom_data_written = true;
     }
     crc16(crc, &v, 1);
@@ -75,7 +95,7 @@ bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, ui
 
 bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
   do {
-    const uint8_t c = eeprom_buffered_read_byte(pos);
+    const uint8_t c = (pos < (int)MARLIN_EEPROM_SIZE) ? eeprom_buffer[pos] : 0xFF;
     if (writing) *value = c;
     crc16(crc, &c, 1);
     pos++;
diff --git a/Marlin/src/HAL/RP2040/pinsDebug.h b/Marlin/src/HAL/RP2040/pinsDebug.h
index f3842c4aff..8f58089fb1 100644
--- a/Marlin/src/HAL/RP2040/pinsDebug.h
+++ b/Marlin/src/HAL/RP2040/pinsDebug.h
@@ -25,7 +25,7 @@
 #include "HAL.h"
 
 #ifndef NUM_DIGITAL_PINS
-   #error "Expected NUM_DIGITAL_PINS not found"
+  #error "Expected NUM_DIGITAL_PINS not found."
 #endif
 
 /**
@@ -74,6 +74,27 @@
  *          signal.  The Arduino pin number is listed by the M43 I command.
  */
 
+/**
+ * Pins Debugging for RP2040
+ *
+ *   - NUMBER_PINS_TOTAL
+ *   - MULTI_NAME_PAD
+ *   - getPinByIndex(index)
+ *   - printPinNameByIndex(index)
+ *   - getPinIsDigitalByIndex(index)
+ *   - digitalPinToAnalogIndex(pin)
+ *   - getValidPinMode(pin)
+ *   - isValidPin(pin)
+ *   - isAnalogPin(pin)
+ *   - digitalRead_mod(pin)
+ *   - pwm_status(pin)
+ *   - printPinPWM(pin)
+ *   - printPinPort(pin)
+ *   - printPinNumber(pin)
+ *   - printPinAnalog(pin)
+ */
+
+#define NUMBER_PINS_TOTAL NUM_DIGITAL_PINS
 #define NUM_ANALOG_FIRST A0
 
 #define MODE_PIN_INPUT  0 // Input mode (reset state)
@@ -81,66 +102,66 @@
 #define MODE_PIN_ALT    2 // Alternate function mode
 #define MODE_PIN_ANALOG 3 // Analog mode
 
-#define PIN_NUM(P) (P & 0x000F)
-#define PIN_NUM_ALPHA_LEFT(P) (((P & 0x000F) < 10) ? ('0' + (P & 0x000F)) : '1')
-#define PIN_NUM_ALPHA_RIGHT(P) (((P & 0x000F) > 9)  ? ('0' + (P & 0x000F) - 10) : 0 )
-#define PORT_NUM(P) ((P  >> 4) & 0x0007)
-#define PORT_ALPHA(P) ('A' + (P  >> 4))
+#define getPinByIndex(x) pin_array[x].pin
+#define printPinNameByIndex(x) do{ sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); }while(0)
+#define getPinIsDigitalByIndex(x) pin_array[x].is_digital
+#define digitalPinToAnalogIndex(P) digital_pin_to_analog_pin(P)
 
-/**
- * Translation of routines & variables used by pinsDebug.h
- */
-#define NUMBER_PINS_TOTAL NUM_DIGITAL_PINS
-#define VALID_PIN(ANUM) (pin_t(ANUM) >= 0 && pin_t(ANUM) < NUMBER_PINS_TOTAL)
-#define digitalRead_mod(Ard_num) extDigitalRead(Ard_num)  // must use Arduino pin numbers when doing reads
-#define PRINT_PIN(Q)
-#define PRINT_PIN_ANALOG(p) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), DIGITAL_PIN_TO_ANALOG_PIN(pin)); SERIAL_ECHO(buffer); }while(0)
-#define DIGITAL_PIN_TO_ANALOG_PIN(ANUM) -1  // will report analog pin number in the print port routine
+uint8_t get_pin_mode(const pin_t pin) {
+  // Check if pin is in alternate function mode (I2C, SPI, etc.)
+  const uint32_t gpio_func = gpio_get_function(pin);
 
-// x is a variable used to search pin_array
-#define GET_ARRAY_IS_DIGITAL(x) ((bool) pin_array[x].is_digital)
-#define GET_ARRAY_PIN(x) ((pin_t) pin_array[x].pin)
-#define PRINT_ARRAY_NAME(x) do{ sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); }while(0)
-#define MULTI_NAME_PAD 33 // space needed to be pretty if not first name assigned to a pin
-
-uint8_t get_pin_mode(const pin_t Ard_num) {
-
-  uint dir = gpio_get_dir( Ard_num);
-
-  if (dir) return MODE_PIN_OUTPUT;
-  else return MODE_PIN_INPUT;
+  // GPIO_FUNC_I2C is typically function 3 on RP2040
+  if ( gpio_func == GPIO_FUNC_I2C
+    || gpio_func == GPIO_FUNC_SPI
+    || gpio_func == GPIO_FUNC_UART
+    || gpio_func == GPIO_FUNC_PWM
+  ) {
+    return MODE_PIN_ALT;
+  }
 
+  // For GPIO mode, check direction
+  return gpio_get_dir(pin) ? MODE_PIN_OUTPUT : MODE_PIN_INPUT;
 }
 
-bool getValidPinMode(const pin_t Ard_num) {
-  const uint8_t pin_mode = get_pin_mode(Ard_num);
+bool getValidPinMode(const pin_t pin) {
+  const uint8_t pin_mode = get_pin_mode(pin);
   return pin_mode == MODE_PIN_OUTPUT || pin_mode == MODE_PIN_ALT;  // assume all alt definitions are PWM
 }
 
-int8_t digital_pin_to_analog_pin(pin_t Ard_num) {
-  Ard_num -= NUM_ANALOG_FIRST;
-  return (Ard_num >= 0 && Ard_num < NUM_ANALOG_INPUTS) ? Ard_num : -1;
+#define isValidPin(P) WITHIN(P, 0, pin_t(NUMBER_PINS_TOTAL - 1))
+
+int8_t digital_pin_to_analog_pin(pin_t pin) {
+  pin -= NUM_ANALOG_FIRST;
+  return (WITHIN(pin, 0, NUM_ANALOG_INPUTS - 1)) ? pin : -1;
 }
 
-bool isAnalogPin(const pin_t Ard_num) {
-  return digital_pin_to_analog_pin(Ard_num) != -1;
+bool isAnalogPin(const pin_t pin) {
+  return digital_pin_to_analog_pin(pin) != -1;
 }
 
-bool is_digital(const pin_t x) {
-  const uint8_t pin_mode = get_pin_mode(x);
-  return pin_mode == MODE_PIN_INPUT || pin_mode == MODE_PIN_OUTPUT;
+#define digitalRead_mod(A) extDigitalRead(A)  // must use Arduino pin numbers when doing reads
+#define printPinNumber(P) do{ sprintf_P(buffer, PSTR("%3d "), P); SERIAL_ECHO(buffer); }while(0)
+#define printPinAnalog(P) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), digitalPinToAnalogIndex(P)); SERIAL_ECHO(buffer); }while(0)
+#define MULTI_NAME_PAD 33 // space needed to be pretty if not first name assigned to a pin
+
+//bool is_digital(const pin_t pin) {
+//  const uint8_t pin_mode = get_pin_mode(pin);
+//  return pin_mode == MODE_PIN_INPUT || pin_mode == MODE_PIN_OUTPUT;
+//}
+
+bool pwm_status(const pin_t pin) {
+  // Check if this pin is configured for PWM
+  return PWM_PIN(pin) && get_pin_mode(pin) == MODE_PIN_ALT;
 }
 
-void printPinPort(const pin_t Ard_num) {
-  SERIAL_ECHOPGM("Pin: ");
-  SERIAL_ECHO(Ard_num);
-}
-
-bool pwm_status(const pin_t Ard_num) {
-  return get_pin_mode(Ard_num) == MODE_PIN_ALT;
-}
-
-void printPinPWM(const pin_t Ard_num) {
-  if (PWM_PIN(Ard_num)) {
+void printPinPWM(const pin_t pin) {
+  if (pwm_status(pin)) {
+    // RP2040 has hardware PWM on specific pins
+    char buffer[22];
+    sprintf_P(buffer, PSTR("PWM:  pin %d  "), pin);
+    SERIAL_ECHO(buffer);
   }
 }
+
+void printPinPort(const pin_t pin) {}
diff --git a/Marlin/src/HAL/RP2040/temp_soc.h b/Marlin/src/HAL/RP2040/temp_soc.h
new file mode 100644
index 0000000000..e182fb88dc
--- /dev/null
+++ b/Marlin/src/HAL/RP2040/temp_soc.h
@@ -0,0 +1,30 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+// RP2040 internal temperature sensor
+// Formula: T = 27 - (ADC_voltage - 0.706) / 0.001721
+// ADC_voltage = (RAW / OVERSAMPLENR) * 3.3 / 4096  (RAW is accumulated over OVERSAMPLENR samples)
+// T = 27 - ((RAW / OVERSAMPLENR) * 3.3 / 4096 - 0.706) / 0.001721
+// Simplified: T = 437.423 - (RAW / OVERSAMPLENR) * 0.46875
+
+#define TEMP_SOC_SENSOR(RAW) (437.423f - ((RAW) / OVERSAMPLENR) * 0.46875f)
diff --git a/Marlin/src/HAL/RP2040/u8g/LCD_defines.h b/Marlin/src/HAL/RP2040/u8g/LCD_defines.h
new file mode 100644
index 0000000000..acdd94b477
--- /dev/null
+++ b/Marlin/src/HAL/RP2040/u8g/LCD_defines.h
@@ -0,0 +1,28 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * RP2040 LCD-specific defines
+ */
+uint8_t u8g_com_rp2040_ssd_i2c_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr); // u8g_com_rp2040_ssd_i2c.cpp
+#define U8G_COM_SSD_I2C_HAL   u8g_com_rp2040_ssd_i2c_fn
diff --git a/Marlin/src/HAL/RP2040/u8g/u8g_com_rp2040_ssd_i2c.cpp b/Marlin/src/HAL/RP2040/u8g/u8g_com_rp2040_ssd_i2c.cpp
new file mode 100644
index 0000000000..ea42bf190d
--- /dev/null
+++ b/Marlin/src/HAL/RP2040/u8g/u8g_com_rp2040_ssd_i2c.cpp
@@ -0,0 +1,108 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * 2-Wire I2C COM Driver
+ *
+ * Handles Hardware I2C on valid pin combinations.
+ * Wire library is used for Hardware I2C.
+ *
+ * Hardware I2C uses pins defined in pins_arduino.h.
+ */
+
+#ifdef __PLAT_RP2040__
+
+#include "../../../inc/MarlinConfig.h"
+
+#if HAS_U8GLIB_I2C_OLED
+
+#include <U8glib-HAL.h>
+
+#include <Wire.h>
+#ifndef MASTER_ADDRESS
+  #define MASTER_ADDRESS 0x01
+#endif
+
+/**
+ * BUFFER_LENGTH is defined in libraries\Wire\utility\WireBase.h
+ * Default value is 32
+ * Increase this value to 144 to send U8G_COM_MSG_WRITE_SEQ in single block
+ */
+#ifndef BUFFER_LENGTH
+  #define BUFFER_LENGTH 32
+#endif
+#if BUFFER_LENGTH > 144
+  #error "BUFFER_LENGTH should not be greater than 144."
+#endif
+#define I2C_MAX_LENGTH (BUFFER_LENGTH - 1)
+
+uint8_t u8g_com_rp2040_ssd_i2c_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr) {
+
+  // Hardware I2C flag
+  //static bool i2c_initialized = false;  // Flag to only run init/linking code once
+  //if (!i2c_initialized) {               // Init runtime linkages
+  //  i2c_initialized = true;             // Only do this once
+  //}
+
+  static uint8_t control;
+  // Use the global Wire instance (already initialized with correct pins for RP2040)
+  switch (msg) {
+    case U8G_COM_MSG_INIT:
+      Wire.setClock(400000);
+      // Wire already initialized in MarlinUI::init(), no need to call begin() again
+      break;
+
+    case U8G_COM_MSG_ADDRESS:           // Define cmd (arg_val = 0) or data mode (arg_val = 1)
+      control = arg_val ? 0x40 : 0x00;
+      break;
+
+    case U8G_COM_MSG_WRITE_BYTE:
+      ::Wire.beginTransmission(0x3C);
+      ::Wire.write(control);
+      ::Wire.write(arg_val);
+      ::Wire.endTransmission();
+      break;
+
+    case U8G_COM_MSG_WRITE_SEQ: {
+      uint8_t* dataptr = (uint8_t*)arg_ptr;
+      while (arg_val > 0) {
+        ::Wire.beginTransmission(0x3C);
+        ::Wire.write(control);
+        if (arg_val <= I2C_MAX_LENGTH) {
+          ::Wire.write(dataptr, arg_val);
+          arg_val = 0;
+        }
+        else {
+          ::Wire.write(dataptr, I2C_MAX_LENGTH);
+          arg_val -= I2C_MAX_LENGTH;
+          dataptr += I2C_MAX_LENGTH;
+        }
+        ::Wire.endTransmission();
+      }
+      break;
+    }
+  }
+  return 1;
+}
+
+#endif // HAS_U8GLIB_I2C_OLED
+#endif // __PLAT_RP2040__
diff --git a/Marlin/src/HAL/STM32/pinsDebug.h b/Marlin/src/HAL/STM32/pinsDebug.h
index b14c9c721c..89e2514af0 100644
--- a/Marlin/src/HAL/STM32/pinsDebug.h
+++ b/Marlin/src/HAL/STM32/pinsDebug.h
@@ -136,10 +136,8 @@ const XrefInfo pin_xref[] PROGMEM = {
 #define printPinNumber(Q)
 #define printPinAnalog(P) do{ sprintf_P(buffer, PSTR(" (A%2d)  "), digitalPinToAnalogIndex(P)); SERIAL_ECHO(buffer); }while(0)
 #define digitalPinToAnalogIndex(P) -1  // will report analog pin number in the print port routine
-
-// x is a variable used to search pin_array
-#define getPinIsDigitalByIndex(x) ((bool) pin_array[x].is_digital)
-#define getPinByIndex(x) ((pin_t) pin_array[x].pin)
+#define getPinIsDigitalByIndex(x) bool(pin_array[x].is_digital)
+#define getPinByIndex(x) pin_t(pin_array[x].pin)
 #define printPinNameByIndex(x) do{ sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); }while(0)
 #define MULTI_NAME_PAD 33 // space needed to be pretty if not first name assigned to a pin
 
@@ -229,8 +227,7 @@ void printPinPort(const pin_t pin) {
     calc_p -= NUM_ANALOG_FIRST;
     if (calc_p > 7) calc_p += 8;
   }
-  SERIAL_ECHOPGM(" M42 P", calc_p);
-  SERIAL_CHAR(' ');
+  SERIAL_ECHO(F(" M42 P"), calc_p, C(' '));
   if (calc_p < 100) {
     SERIAL_CHAR(' ');
     if (calc_p <  10)
diff --git a/Marlin/src/core/boards.h b/Marlin/src/core/boards.h
index f22c9fd1f1..6c51cb01a4 100644
--- a/Marlin/src/core/boards.h
+++ b/Marlin/src/core/boards.h
@@ -578,7 +578,8 @@
 //
 
 #define BOARD_RP2040                  6200  // Generic RP2040 Test board
-#define BOARD_BTT_SKR_PICO            6201  // BigTreeTech SKR Pico 1.x
+#define BOARD_RASPBERRY_PI_PICO       6201  // Raspberry Pi Pico
+#define BOARD_BTT_SKR_PICO            6202  // BigTreeTech SKR Pico 1.x
 
 //
 // Custom board
diff --git a/Marlin/src/lcd/marlinui.cpp b/Marlin/src/lcd/marlinui.cpp
index f4d4c28fa7..8a6d18dc2d 100644
--- a/Marlin/src/lcd/marlinui.cpp
+++ b/Marlin/src/lcd/marlinui.cpp
@@ -260,7 +260,11 @@ constexpr uint8_t epps = ENCODER_PULSES_PER_STEP;
 void MarlinUI::init() {
 
   #if HAS_U8GLIB_I2C_OLED && PINS_EXIST(I2C_SCL, I2C_SDA) && DISABLED(SOFT_I2C_EEPROM)
-    Wire.begin(uint8_t(I2C_SDA_PIN), uint8_t(I2C_SCL_PIN));
+    #ifdef TARGET_RP2040
+      Wire.begin();  // RP2040 MbedI2C uses pins configured in pins_arduino.h
+    #else
+      Wire.begin(uint8_t(I2C_SDA_PIN), uint8_t(I2C_SCL_PIN));
+    #endif
   #endif
 
   init_lcd();
diff --git a/Marlin/src/pins/mega/pins_GT2560_V3.h b/Marlin/src/pins/mega/pins_GT2560_V3.h
index ae4614eedd..81774006df 100644
--- a/Marlin/src/pins/mega/pins_GT2560_V3.h
+++ b/Marlin/src/pins/mega/pins_GT2560_V3.h
@@ -162,8 +162,9 @@
 #endif
 
 //
-// LCD Controller
+// LCD / Controller
 //
+
 #define BEEPER_PIN                            18
 
 #if ENABLED(YHCB2004)
diff --git a/Marlin/src/pins/mega/pins_INTAMSYS40.h b/Marlin/src/pins/mega/pins_INTAMSYS40.h
index 83a77ec98c..cfb4d0186e 100644
--- a/Marlin/src/pins/mega/pins_INTAMSYS40.h
+++ b/Marlin/src/pins/mega/pins_INTAMSYS40.h
@@ -116,7 +116,7 @@
 #endif
 
 //
-// LCD Controller
+// LCD / Controller
 //
 
 #define BEEPER_PIN                            18
diff --git a/Marlin/src/pins/pins.h b/Marlin/src/pins/pins.h
index e73a00ae81..56c4b78dff 100644
--- a/Marlin/src/pins/pins.h
+++ b/Marlin/src/pins/pins.h
@@ -949,6 +949,8 @@
 
 #elif MB(RP2040)
   #include "rp2040/pins_RP2040.h"                   // RP2040                               env:RP2040
+#elif MB(RASPBERRY_PI_PICO)
+  #include "rp2040/pins_RASPBERRY_PI_PICO.h"        // RP2040                               env:RP2040
 #elif MB(BTT_SKR_PICO)
   #include "rp2040/pins_BTT_SKR_Pico.h"             // RP2040                               env:SKR_Pico env:SKR_Pico_UART
 
diff --git a/Marlin/src/pins/rp2040/pins_RASPBERRY_PI_PICO.h b/Marlin/src/pins/rp2040/pins_RASPBERRY_PI_PICO.h
new file mode 100644
index 0000000000..daede9f560
--- /dev/null
+++ b/Marlin/src/pins/rp2040/pins_RASPBERRY_PI_PICO.h
@@ -0,0 +1,171 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "env_validate.h"
+
+#define BOARD_INFO_NAME "Pi Pico"
+#define DEFAULT_MACHINE_NAME "Pi Pico"
+
+#ifndef MARLIN_EEPROM_SIZE
+  #define MARLIN_EEPROM_SIZE             0x1000U  // 4K
+  #define FLASH_EEPROM_EMULATION
+#endif
+
+//
+// Limit Switches
+//
+#define X_STOP_PIN                             0  // GP0
+#define Y_STOP_PIN                             1  // GP1
+#define Z_STOP_PIN                             2  // GP2
+
+//
+// Steppers
+//
+#define X_STEP_PIN                             3  // GP3
+#define X_DIR_PIN                              6  // GP6
+#define X_ENABLE_PIN                           7  // GP7
+
+#define Y_STEP_PIN                             8  // GP8
+#define Y_DIR_PIN                              9  // GP9
+#define Y_ENABLE_PIN                X_ENABLE_PIN
+
+#define Z_STEP_PIN                            10  // GP10
+#define Z_DIR_PIN                             11  // GP11
+#define Z_ENABLE_PIN                X_ENABLE_PIN
+
+#define E0_STEP_PIN                           12  // GP12
+#define E0_DIR_PIN                            13  // GP13
+#define E0_ENABLE_PIN               X_ENABLE_PIN
+
+//
+// Heaters / Fans
+//
+#define HEATER_0_PIN                          14  // GP14
+#define HEATER_BED_PIN                        15  // GP15
+#define FAN0_PIN                              28  // GP28
+
+//
+// Temperature Sensors
+//
+#define TEMP_0_PIN                            A0  // GP26 - Analog Input
+#define TEMP_BED_PIN                          A1  // GP27 - Analog Input
+
+//
+// Misc. Functions
+//
+#define LED_PIN                               25  // GP25
+
+//
+// SD Card
+//
+#define SD_DETECT_PIN                         -1  // No pins left
+#define SDCARD_CONNECTION ONBOARD
+#define SD_SS_PIN                             17  // GP17 - SPI0_CS for SD card chip select
+
+//
+// LCD / Controller
+//
+
+#if ENABLED(U8GLIB_SSD1306)
+  #if !IS_ULTIPANEL
+    #error "Add '#define IS_ULTIPANEL 1' to Configuration.h to enable Marlin UI menus and encoder support."
+  #endif
+  #if IS_NEWPANEL
+    #define BTN_EN1                           20  // GP20 - Encoder A phase
+    #define BTN_EN2                           21  // GP21 - Encoder B phase
+    #define BTN_ENC                           22  // GP22 - Encoder push button
+  #endif
+
+  #define ALTERNATIVE_LCD // Use default hardware I2C port
+#endif // U8GLIB_SSD1306
+
+/*
+┌───────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+│                                  RASPBERRY PI PICO - PHYSICAL PIN MAPPING                                 │
+├──────────────┬───────────┬───────────┬───────────┬───────────┬────────────────────────────────────────────┤
+│ Physical Pin │   GPIO    │   ALT0    │   ALT1    │   ALT2    │                Marlin Usage                │
+├──────────────┼───────────┼───────────┼───────────┼───────────┼────────────────────────────────────────────┤
+│       1      │   GP0     │  I2C0_SDA │ SPI0_MISO │ UART0_TX  │ X_STOP_PIN                                 │
+│       2      │   GP1     │  I2C0_SCL │ SPI0_CS   │ UART0_RX  │ Y_STOP_PIN                                 │
+│       3      │   GND     │           │           │           │                                            │
+│       4      │   GP2     │  I2C1_SDA │ SPI0_SCK  │           │ Z_STOP_PIN                                 │
+│       5      │   GP3     │  I2C1_SCL │ SPI0_MOSI │           │ X_STEP_PIN                                 │
+│       6      │   GP4     │  I2C0_SDA │ SPI0_MISO │ UART1_TX  │ SDA_PIN                                    │
+│       7      │   GP5     │  I2C0_SCL │ SPI0_CS   │ UART1_RX  │ SCL_PIN                                    │
+│       8      │   GND     │           │           │           │                                            │
+│       9      │   GP6     │  I2C1_SDA │ SPI0_SCK  │           │ X_DIR_PIN                                  │
+│      10      │   GP7     │  I2C1_SCL │ SPI0_MOSI │           │ X_ENABLE_PIN                               │
+│      11      │   GP8     │  I2C0_SDA │ SPI1_MISO │ UART1_TX  │ Y_STEP_PIN                                 │
+│      12      │   GP9     │  I2C0_SCL │ SPI1_CS   │ UART1_RX  │ Y_DIR_PIN                                  │
+│      13      │   GND     │           │           │           │                                            │
+│      14      │   GP10    │  I2C1_SDA │ SPI1_SCK  │           │ Z_STEP_PIN                                 │
+│      15      │   GP11    │  I2C1_SCL │ SPI1_MOSI │           │ Z_DIR_PIN                                  │
+│      16      │   GP12    │  I2C0_SDA │ SPI1_MISO │ UART0_TX  │ E0_STEP_PIN                                │
+│      17      │   GP13    │  I2C0_SCL │ SPI1_CS   │ UART0_RX  │ E0_DIR_PIN                                 │
+│      18      │   GND     │           │           │           │                                            │
+│      19      │   GP14    │  I2C1_SDA │ SPI1_SCK  │           │ HEATER_0_PIN                               │
+│      20      │   GP15    │  I2C1_SCL │ SPI1_MOSI │           │ HEATER_BED_PIN                             │
+│      21      │   GP16    │  I2C0_SDA │ SPI0_MISO │ UART0_TX  │ SD_MISO_PIN                                │
+│      22      │   GP17    │  I2C0_SCL │ SPI0_CS   │ UART0_RX  │ SD_SS_PIN                                  │
+│      23      │   GND     │           │           │           │                                            │
+│      24      │   GP18    │  I2C1_SDA │ SPI0_SCK  │           │ SD_SCK_PIN                                 │
+│      25      │   GP19    │  I2C1_SCL │ SPI0_MOSI │           │ SD_MOSI_PIN                                │
+│      26      │   GP20    │  I2C0_SDA │           │           │ BTN_EN1 (Encoder A)                        │
+│      27      │   GP21    │  I2C0_SCL │           │           │ BTN_EN2 (Encoder B)                        │
+│      28      │   GND     │           │           │           │                                            │
+│      29      │   GP22    │           │           │           │ BTN_ENC (Encoder Button)                   │
+│      30      │   RUN     │           │           │           │ Reset (Active Low)                         │
+│      31      │   GP26    │   ADC0    │ I2C1_SDA  │           │ TEMP_0_PIN (A0)                            │
+│      32      │   GP27    │   ADC1    │ I2C1_SCL  │           │ TEMP_BED_PIN (A1)                          │
+│      33      │   GND     │           │           │           │                                            │
+│      34      │   GP28    │   ADC2    │           │           │ FAN0_PIN                                   │
+│      35      │   ADC_VREF│           │           │           │ ADC Reference Voltage                      │
+│      36      │   3V3     │           │           │           │ 3.3V Power Output                          │
+│      37      │   3V3_EN  │           │           │           │ 3.3V Enable (Active High)                  │
+│      38      │   GND     │           │           │           │                                            │
+│      39      │   VSYS    │           │           │           │ System Voltage Input (1.8-5.5V)            │
+│      40      │   VBUS    │           │           │           │ USB Bus Voltage (5V when USB connected)    │
+├──────────────┴───────────┴───────────┴───────────┴───────────┴────────────────────────────────────────────┤
+│ Special pin notes for Raspberry Pi Pico                                                                   │
+├───────────────────────────────────────────────────────────────────────────────────────────────────────────┤
+│ • GP23 OP Controls the on-board SMPS Power Save pin. Should not be used for other purposes.               │
+│ • GP24 IP VBUS sense - high if VBUS is present, else low. Should not be used for other purposes.          │
+│ • GP25 OP Connected to user LED. Can be used with board modifications, is not broken out.                 │
+│ • GP29 IP Used in ADC mode (ADC3) to measure VSYS/3. Should not be used for other purposes.               │
+│ • ADC4 (Internal) is connected to the chip's internal temperature sensor.                                 │
+├───────────────────────────────────────────────────────────────────────────────────────────────────────────┤
+│ Marlin pin notes                                                                                          │
+├───────────────────────────────────────────────────────────────────────────────────────────────────────────┤
+│ Shared enable pins:                                                                                       │
+│ • GP7: X_ENABLE_PIN. All stepper drivers use a shared single enable pin X_ENABLE_PIN for pin conservation │
+│                                                                                                           │
+│ Hardware I2C and SPI configuration:                                                                       │
+│   These are hardcoded in:                                                                                 │
+│ .platformio/packages/framework-arduino-mbed/variants/RASPBERRY_RASPBERRY_PI_PICO/pins_arduino.h           │
+│ • GP4: SDA           default: "#define PIN_WIRE_SDA        (4u)"                                          │
+│ • GP5: SCL           default: "#define PIN_WIRE_SCL        (5u)"                                          │
+│ • GP16: MISO         default: "#define PIN_SPI_MISO        (16u)"                                         │
+│ • GP18: SCK          default: "#define PIN_SPI_SCK         (18u)"                                         │
+│ • GP19: MOSI         default: "#define PIN_SPI_MOSI        (19u)"                                         │
+└───────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+*/
diff --git a/Marlin/src/pins/rp2040/pins_RP2040.h b/Marlin/src/pins/rp2040/pins_RP2040.h
index 6a4e54f0bd..95de85b4bf 100644
--- a/Marlin/src/pins/rp2040/pins_RP2040.h
+++ b/Marlin/src/pins/rp2040/pins_RP2040.h
@@ -89,10 +89,7 @@
 #define TEMP_2_PIN                            A2  // Analog Input
 #define TEMP_BED_PIN                          A1  // Analog Input
 
-#define TEMP_MCU      HAL_ADC_MCU_TEMP_DUMMY_PIN  // this is a flag value, don´t change
-
 #define TEMP_CHAMBER_PIN              TEMP_1_PIN
-#define TEMP_BOARD_PIN                  TEMP_MCU
 
 // SPI for MAX Thermocouple
 #if !HAS_MEDIA
@@ -560,3 +557,28 @@
   #endif // IS_NEWPANEL
 
 #endif // HAS_WIRED_LCD
+
+/*
+┌───────────────────────────────────────────────────────────────────────────────────────────────────────────────┐
+│                                     PIN CONFLICTS and ERRORS                                                  │
+├───────────────────────────────────────────────────────────────────────────────────────────────────────────────┤
+│                                                                                                               │
+│ VIRTUAL PINS - NOT REAL GPIO:                                                                                 │
+│ • GP40+: E_MUX pins, TMC_SW pins are virtual/extended pins, not physical RP2040 GPIO                          │
+│ • GP64, GP66: TMC Software SPI pins - these don't exist on RP2040 hardware                                    │
+│                                                                                                               │
+│ MULTIPLE ASSIGNMENTS - REVIEW NEEDED:                                                                         │
+│ • GP4:  Z_DIR_PIN + Z_CS_PIN + SPINDLE_LASER_ENA_PIN (conditional conflicts)                                  │
+│ • GP5:  Z_STEP_PIN + FILWIDTH_PIN + SPINDLE_DIR_PIN (conditional conflicts)                                   │
+│ • GP6:  CASE_LIGHT_PIN + SPINDLE_LASER_PWM_PIN (conditional - both PWM)                                       │
+│ • GP21: FAN1_PIN + FIL_RUNOUT_PIN (may conflict if both features enabled)                                     │
+│ • GP29: ALL assigned to same pin:                                                                             │
+│   - X_STEP_PIN, X_DIR_PIN, X_ENABLE_PIN, X_CS_PIN (4 pins)                                                    │
+│   - Y_STEP_PIN, Y_DIR_PIN, Y_ENABLE_PIN, Y_CS_PIN (4 pins)                                                    │
+│   - E0_STEP_PIN, E0_DIR_PIN, E0_ENABLE_PIN, E0_CS_PIN (4 pins)                                                │
+│   - LCD_PINS_EN (CR10_STOCKDISPLAY), LCD_PINS_D7, DOGLCD_CS (ELB_FULL_GRAPHIC_CONTROLLER)                     │
+│   → 12+ critical functions sharing ONE GPIO - PRINTER CANNOT FUNCTION!                                        │
+└───────────────────────────────────────────────────────────────────────────────────────────────────────────────┘
+*/
+
+#error "Pin assignments for this board are not for practical use. See comments in pins_RP2040.h"
diff --git a/Marlin/src/sd/SdBaseFile.h b/Marlin/src/sd/SdBaseFile.h
index dc31e8492d..e2dbf489f1 100644
--- a/Marlin/src/sd/SdBaseFile.h
+++ b/Marlin/src/sd/SdBaseFile.h
@@ -46,6 +46,19 @@ struct filepos_t {
   filepos_t() : position(0), cluster(0) {}
 };
 
+// Avoid conflict with RP2040 / newlib fcntl.h
+#ifdef __PLAT_RP2040__
+  #undef O_RDONLY
+  #undef O_WRONLY
+  #undef O_RDWR
+  #undef O_ACCMODE
+  #undef O_APPEND
+  #undef O_SYNC
+  #undef O_TRUNC
+  #undef O_CREAT
+  #undef O_EXCL
+#endif
+
 // use the gnu style oflag in open()
 uint8_t const O_READ = 0x01,                    // open() oflag for reading
               O_RDONLY = O_READ,                // open() oflag - same as O_IN
diff --git a/Marlin/src/sd/SdFatStructs.h b/Marlin/src/sd/SdFatStructs.h
index b3f94b57a0..bacff4e1c0 100644
--- a/Marlin/src/sd/SdFatStructs.h
+++ b/Marlin/src/sd/SdFatStructs.h
@@ -32,7 +32,9 @@
 
 #include <stdint.h>
 
-#define PACKED __attribute__((__packed__))
+#ifndef PACKED
+  #define PACKED __attribute__((__packed__))
+#endif
 
 /**
  * mostly from Microsoft document fatgen103.doc
diff --git a/ini/raspberrypi.ini b/ini/raspberrypi.ini
index 059f4d1821..2ee74631f9 100644
--- a/ini/raspberrypi.ini
+++ b/ini/raspberrypi.ini
@@ -16,12 +16,13 @@ build_src_filter = ${common.default_src_filter} +<src/HAL/RP2040>
 lib_deps         = ${common.lib_deps}
                    arduino-libraries/Servo
                    https://github.com/pkElectronics/SoftwareSerialM#master
+                   #adafruit/Adafruit TinyUSB Library
                    #lvgl/lvgl@^8.1.0
 lib_ignore       = WiFi
-build_flags      = ${common.build_flags} -D__PLAT_RP2040__ -DPLATFORM_M997_SUPPORT -Wno-expansion-to-defined -Wno-vla -Wno-ignored-qualifiers
+build_flags      = ${common.build_flags} -D__PLAT_RP2040__ -DPLATFORM_M997_SUPPORT -DNO_SD_HOST_DRIVE -Wno-expansion-to-defined -Wno-vla -Wno-ignored-qualifiers
 #debug_tool      = jlink
 #upload_protocol = jlink
-custom_marlin.HAS_SD_HOST_DRIVE = tinyusb
+#custom_marlin.HAS_SD_HOST_DRIVE = tinyusb
 
 [env:RP2040-alt]
 extends          = env:RP2040