improve logging

CMakeLists.txt

@@ -35,11 +35,15 @@ pico_sdk_init()
 
 # Add executable. Default name is the project name, version 0.1
 
-if (TARGET tinyusb_device)
+if (TARGET tinyusb_host)
             add_executable(hello_usb
                 hello_usb.cpp
                 display.cpp
                 commands/echo.cpp
+                keyboard_input.cpp
+                command_processor.cpp
+                epaper_manager.cpp
+                wifi_manager.cpp
                 )
 
     add_subdirectory(pico-ssd1306 commands)
@@ -50,6 +54,7 @@ if (TARGET tinyusb_device)
 
     # Add include directories for e-Paper
     target_include_directories(hello_usb PRIVATE 
+        ${CMAKE_CURRENT_SOURCE_DIR}
         ${CMAKE_CURRENT_SOURCE_DIR}/Pico_ePaper_Code/c/lib/Config
         ${CMAKE_CURRENT_SOURCE_DIR}/Pico_ePaper_Code/c/lib/e-Paper
         ${CMAKE_CURRENT_SOURCE_DIR}/Pico_ePaper_Code/c/lib/Fonts
@@ -57,11 +62,11 @@ if (TARGET tinyusb_device)
     )
 
     # pull in common dependencies
-    target_link_libraries(hello_usb pico_stdlib pico_ssd1306 hardware_i2c Config ePaper GUI Fonts hardware_spi pico_multicore)
+    target_link_libraries(hello_usb pico_stdlib pico_ssd1306 hardware_i2c Config ePaper GUI Fonts hardware_spi pico_multicore pico_flash tinyusb_host tinyusb_board pico_cyw43_arch_lwip_threadsafe_background)
 
     # enable usb output, disable uart output
-    pico_enable_stdio_usb(hello_usb 1)
-    pico_enable_stdio_uart(hello_usb 0)
+    pico_enable_stdio_usb(hello_usb 0)
+    pico_enable_stdio_uart(hello_usb 1)
 
     # create map/bin/hex/uf2 file etc.
     pico_add_extra_outputs(hello_usb)

DISPLAY_REFRESH.md

@@ -0,0 +1,84 @@
+# Display Refresh Mechanism
+
+This document explains the dual-core architecture used to handle USB keyboard input and e-Paper display updates efficiently on the Raspberry Pi Pico.
+
+## Architecture Overview
+
+The system utilizes both cores of the RP2040 to ensure that the slow refresh rate of the e-Paper display does not block or lag the USB keyboard input.
+
+### Core 0: Input Handling (Producer)
+
+*   **Role:** Handles USB Host tasks, processes keyboard reports, and manages the text buffer.
+*   **Behavior:**
+    1.  Receives key presses via TinyUSB callbacks.
+    2.  Updates the local text buffer (`g_entry_list`).
+    3.  Triggers a display update via `send_display_update()`.
+*   **Non-Blocking Transmission:**
+    *   When an update is needed, Core 0 allocates a `DisplayMessage` on the heap.
+    *   It attempts to push the message pointer to the Multicore FIFO.
+    *   **Critical Optimization:** It uses `multicore_fifo_wready()` to check if the FIFO has space.
+        *   **If Ready:** Pushes the message.
+        *   **If Full:** Immediately frees the message and skips the update. This ensures Core 0 never waits for Core 1, keeping typing responsive.
+
+### Core 1: Display Driver (Consumer)
+
+*   **Role:** Manages the e-Paper hardware and performs the actual drawing operations.
+*   **Behavior:**
+    1.  Initializes the e-Paper display.
+    2.  Waits for messages in the Multicore FIFO.
+*   **Smart Refresh (Accumulation):**
+    *   When Core 1 wakes up to process a message, it first checks if *more* messages have arrived while it was sleeping or busy.
+    *   **FIFO Draining:** It loops through the FIFO, popping and freeing all intermediate messages, keeping only the **latest** one.
+    *   This ensures that if the user types "Hello World" quickly, Core 1 might skip rendering "Hello " and jump straight to rendering "Hello World", preventing a queue of obsolete updates from slowing down the display.
+
+## Data Flow Diagram
+
+```mermaid
+sequenceDiagram
+    participant User
+    participant Core0 as Core 0 (USB/Input)
+    participant FIFO as Multicore FIFO
+    participant Core1 as Core 1 (Display)
+
+    User->>Core0: Types 'A'
+    Core0->>FIFO: Push Msg('A')
+    
+    User->>Core0: Types 'B'
+    Core0->>FIFO: Push Msg('AB')
+    
+    Note over Core1: Busy refreshing...
+    
+    User->>Core0: Types 'C'
+    alt FIFO is Full
+        Core0->>Core0: Drop Msg('ABC') (Free memory)
+    else FIFO has space
+        Core0->>FIFO: Push Msg('ABC')
+    end
+
+    Core1->>FIFO: Pop Msg('A')
+    Note over Core1: Checks FIFO for newer msgs
+    FIFO->>Core1: Msg('AB') exists
+    Core1->>Core1: Free Msg('A'), use Msg('AB')
+    
+    FIFO->>Core1: Msg('ABC') exists
+    Core1->>Core1: Free Msg('AB'), use Msg('ABC')
+    
+    Core1->>Display: Render('ABC')
+```
+
+## Key Functions
+
+*   **`send_display_update(const char *entry, bool finish_line)`**: 
+    *   Allocates memory.
+    *   Checks FIFO status.
+    *   Pushes or drops message.
+*   **`core1_display_init()`**: 
+    *   Main loop for Core 1.
+    *   Drains FIFO to find the latest message.
+    *   Calls e-Paper drawing functions.
+
+## Memory Management
+
+*   Messages are `malloc`'d by Core 0.
+*   Messages are `free`'d by Core 1 (after processing or dropping).
+*   If Core 0 drops a message because the FIFO is full, it `free`s it immediately.

command_processor.cpp

@@ -0,0 +1,17 @@
+#include "command_processor.h"
+#include <string.h>
+#include <stdio.h>
+
+CommandAction parse_command(const char* input) {
+    if (input[0] != '/') {
+        return CMD_NONE;
+    }
+
+    if (strcmp(input, "/refresh") == 0) return CMD_REFRESH;
+    if (strcmp(input, "/clear") == 0) return CMD_CLEAR;
+    if (strcmp(input, "/scan") == 0) return CMD_SCAN;
+    if (strncmp(input, "/connect ", 9) == 0 || strcmp(input, "/connect") == 0) return CMD_CONNECT;
+    if (strcmp(input, "/status") == 0) return CMD_STATUS;
+    
+    return CMD_UNKNOWN;
+}

command_processor.h

@@ -0,0 +1,20 @@
+#ifndef COMMAND_PROCESSOR_H
+#define COMMAND_PROCESSOR_H
+
+enum CommandAction {
+    CMD_NONE,
+    CMD_REFRESH,
+    CMD_CLEAR,
+    CMD_SCAN,
+    CMD_CONNECT,
+    CMD_STATUS,
+    CMD_UNKNOWN
+};
+
+/**
+ * Parses a string to check if it is a command.
+ * Returns the corresponding CommandAction.
+ */
+CommandAction parse_command(const char* input);
+
+#endif // COMMAND_PROCESSOR_H

epaper_manager.cpp

@@ -0,0 +1,272 @@
+#include "epaper_manager.h"
+#include "wifi_manager.h"
+#include "pico/stdlib.h"
+#include "pico/multicore.h"
+#include "pico/flash.h"
+#include "pico/util/queue.h"
+#include <stdlib.h>
+#include <string.h>
+#include <stdio.h>
+
+// e-Paper library includes
+extern "C" {
+    #include "DEV_Config.h"
+    #include "EPD_7in5b_V2.h"
+    #include "GUI_Paint.h"
+}
+
+// e-Paper display buffers
+static UBYTE *g_epd_image = NULL;  // Black image buffer
+static UBYTE *g_epd_red = NULL;    // Red image buffer
+
+// Entry list for display
+#define MAX_ENTRIES 15
+#define ENTRY_LENGTH 64
+typedef struct {
+    char entries[MAX_ENTRIES][ENTRY_LENGTH];
+    int count;
+} EntryList;
+
+static EntryList g_entry_list = {{}, 0};
+static bool g_force_full_refresh = false;  // Flag to force full refresh when list is full
+
+// Synchronization flag for multicore initialization
+static volatile bool g_display_ready = false;
+
+// Queue for display messages (replacing raw FIFO to avoid conflict with flash_safe_execute)
+static queue_t g_display_queue;
+#define QUEUE_LENGTH 8
+
+// Display update message structure for inter-core communication
+typedef struct {
+    EntryList entries;
+    bool use_partial;  // Use partial refresh instead of full refresh
+    UWORD xstart;      // Partial refresh region
+    UWORD ystart;
+    UWORD xend;
+    UWORD yend;
+} DisplayMessage;
+
+static void init_epaper_display() {
+    printf("[Core 1] Initializing 7.5\" e-Paper display (B V2)...\r\n");
+    
+    // Initialize the hardware
+    if (DEV_Module_Init() != 0) {
+        printf("[Core 1] Failed to initialize e-Paper hardware!\r\n");
+        return;
+    }
+    
+    // Initialize the display
+    printf("[Core 1] EPD_7IN5B_V2_Init()\r\n");
+    EPD_7IN5B_V2_Init_Fast();
+    printf("[Core 1] EPD_7IN5B_V2_Clear()\r\n");
+    
+    // Create image buffers for black and red content
+    // 7.5" display: 800x480, 8 pixels per byte, so (800/8) * 480 = 48000 bytes each
+    UWORD imagesize = (EPD_7IN5B_V2_WIDTH / 8) * EPD_7IN5B_V2_HEIGHT;
+    
+    g_epd_image = (UBYTE *)malloc(imagesize);
+    g_epd_red = (UBYTE *)malloc(imagesize);
+    
+    if (g_epd_image == NULL || g_epd_red == NULL) {
+        printf("[Core 1] Failed to allocate memory for e-Paper image buffers!\r\n");
+        return;
+    }
+    
+    // Initialize red buffer to all white (0xFF = no red pixels)
+    for (UWORD i = 0; i < imagesize; i++) {
+        g_epd_red[i] = 0xFF;
+    }
+    
+    // Setup paint buffer for black content
+    printf("[Core 1] White background\r\n");
+    Paint_NewImage(g_epd_image, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT, 0, WHITE);
+    Paint_SelectImage(g_epd_image);
+    Paint_Clear(WHITE);
+    
+    // Draw header
+    EPD_7IN5B_V2_Init_Part();
+    EPD_7IN5B_V2_Display_Partial(g_epd_image, 0, 0, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT);
+    EPD_7IN5B_V2_Display_Partial(g_epd_image, 0, 0, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT);
+    EPD_7IN5B_V2_Display_Partial(g_epd_image, 0, 0, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT);
+
+    printf("[Core 1] Trying to connect to wifi\r\n");
+    bool connected = wifi_try_auto_connect();
+    printf("[Core 1] Connected: %d\r\n", connected);
+    
+
+    Paint_SelectImage(g_epd_red);
+    printf("[Core 1] Drawing header\r\n");
+    if (connected) {
+        Paint_DrawString_EN(10, 10, "What's new today: ...", &Font24, WHITE, RED);
+    } else {
+        Paint_DrawString_EN(10, 10, "What's new today:", &Font24, WHITE, RED);
+    }
+    
+    
+    // Display the image with both black and red buffers
+    EPD_7IN5B_V2_Display_Partial(g_epd_red, 0, 0, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT);
+    
+    printf("[Core 1] e-Paper display ready!\r\n");
+}
+
+/**
+ * Core 1 function: Runs display initialization and update handling
+ */
+static void core1_display_init() {
+    // Initialize flash safe execute support for this core
+    flash_safe_execute_core_init();
+
+    // Initialize WiFi on Core 1 so IRQs are handled here
+    wifi_init();
+
+    init_epaper_display();
+    g_display_ready = true;
+    
+    printf("[Core 1] Display ready, waiting for update messages...\n");
+    
+    // Initialize for partial refresh on second call
+    EPD_7IN5B_V2_Init_Part();
+    
+    // Core 1 main loop: handle display updates via Queue
+    while (true) {
+        DisplayMessage *msg;
+        // Check if there's a message in the queue
+        if (queue_try_remove(&g_display_queue, &msg)) {
+            
+            // Drain Queue to get the latest message
+            DisplayMessage *next_msg;
+            while (queue_try_remove(&g_display_queue, &next_msg)) {
+                 printf("[Core 1] Skipping intermediate update\n");
+                 free(msg); // Free the stale message
+                 msg = next_msg;
+            }
+            
+            printf("[Core 1] Updating display with %d entries\n", msg->entries.count);
+            
+            // Update the e-Paper display
+            if (g_epd_image != NULL && g_epd_red != NULL) {
+                // For partial refresh, only clear the text area
+                UWORD y_start = msg->ystart;
+                UWORD y_end = msg->yend;
+                
+                Paint_SelectImage(g_epd_image);
+                Paint_Clear(WHITE);
+                
+                // Calculate offset for partial refresh
+                UBYTE *image_ptr = g_epd_image + (msg->ystart * (EPD_7IN5B_V2_WIDTH / 8));
+
+                if(!msg->use_partial){
+                    // for loop 5 times display white partial
+                    int i = 0;
+                    for(i = 0; i < 1; i++){
+                        EPD_7IN5B_V2_Display_Partial(image_ptr, msg->xstart, msg->ystart, msg->xend, msg->yend);
+                    }
+                }
+                
+                // Draw all entries starting below header
+                UWORD y_pos = 0;
+                // paint only the last 10 entries
+                int start_index = msg->entries.count > 10 ? msg->entries.count - 10 : 0;
+                for (int i = start_index; i < msg->entries.count; i++) {
+                    if (y_pos + 25 < 480) {  //Don't draw beyond screen
+                        Paint_DrawString_EN(20, 50 + i*25, msg->entries.entries[i], &Font16, WHITE, BLACK);
+                        y_pos += 25;  // Space between entries
+                    } else {
+                        printf("[Core 1] Skipping entry to avoid overflow\n");
+                    }
+                }
+                // Use partial or full refresh
+                printf("[Core 1] Using partial refresh\n");
+                EPD_7IN5B_V2_Display_Partial(image_ptr, msg->xstart, msg->ystart, msg->xend, msg->yend);
+            }
+            
+            // Free the message (it was allocated by core 0)
+            free(msg);
+        }
+        
+        sleep_ms(10);
+    }
+}
+
+void epaper_start_background_thread() {
+    // Initialize the queue before starting the thread
+    queue_init(&g_display_queue, sizeof(DisplayMessage*), QUEUE_LENGTH);
+
+    printf("[Core 0] Launching e-Paper display init on core 1...\n");
+    multicore_launch_core1(core1_display_init);
+}
+
+void epaper_send_update(const char *entry, bool finish_line) {
+    if (!g_display_ready) return;  // Don't send if display isn't ready
+    // printf("[Core 0] Preparing display update: '%s' (finish_line=%d)\n", entry, finish_line);
+    
+    // Check if list is at capacity
+    if (g_entry_list.count >= MAX_ENTRIES) {
+        // List is full - clear all entries and start fresh
+        printf("[Core 0] List is FULL - clearing all entries and starting fresh\n");
+        g_entry_list.count = 0;
+        g_force_full_refresh = true;
+    }
+    
+    // Update the current entry (at g_entry_list.count)
+    strncpy(g_entry_list.entries[g_entry_list.count], entry, ENTRY_LENGTH - 1);
+    g_entry_list.entries[g_entry_list.count][ENTRY_LENGTH - 1] = '\0';
+    
+    // Allocate message structure
+    DisplayMessage *msg = (DisplayMessage *)malloc(sizeof(DisplayMessage));
+    if (msg == NULL) {
+        printf("[Core 0] Failed to allocate display message!\n");
+        return;
+    }
+    
+    // Copy entry list to message
+    msg->entries = g_entry_list;
+    // We want to show the current line being edited, so we treat count as count + 1 for display purposes
+    msg->entries.count = g_entry_list.count + 1;
+    
+    // Decide whether to use partial or full refresh
+    msg->use_partial = !g_force_full_refresh;
+    
+    if (g_force_full_refresh) {
+        printf("[Core 0] Forcing full refresh this update\n");
+        g_force_full_refresh = false;  // Reset flag after setting it in message
+        
+        // Full text area refresh
+        msg->xstart = 0;
+        msg->ystart = 50;      // Start below the header
+        msg->xend = 800;       // Full width
+        msg->yend = 480;       // Full height from header onwards
+    } else {
+        // Partial refresh of ONLY the current line
+        msg->xstart = 0;
+        msg->ystart = 50 + (g_entry_list.count * 25);
+        msg->xend = 800;
+        msg->yend = msg->ystart + 25;
+    }
+    
+    // Send message pointer to core 1 via Queue
+    if (queue_try_add(&g_display_queue, &msg)) {
+        // printf("[Core 0] Display update sent to core 1\n");
+    } else {
+        printf("[Core 0] Queue full, skipping display update\n");
+        free(msg);
+    }
+    
+    // If finishing the line, increment count for next time
+    if (finish_line) {
+        g_entry_list.count++;
+    }
+}
+
+void epaper_clear() {
+    g_entry_list.count = 0;
+    memset(g_entry_list.entries, 0, sizeof(g_entry_list.entries));
+    g_force_full_refresh = true;
+    epaper_send_update("", false);
+}
+
+void epaper_force_refresh() {
+    g_force_full_refresh = true;
+    epaper_send_update("", false);
+}

epaper_manager.h

@@ -0,0 +1,31 @@
+#ifndef EPAPER_MANAGER_H
+#define EPAPER_MANAGER_H
+
+#include <stdbool.h>
+
+/**
+ * Launches the e-Paper display handling loop on Core 1.
+ * This function returns immediately after launching the core.
+ */
+void epaper_start_background_thread();
+
+/**
+ * Sends an update to the e-Paper display.
+ * @param entry The text content of the current line.
+ * @param finish_line If true, the line is committed (moved to the list of static lines).
+ *                    If false, it updates the current line being typed.
+ */
+void epaper_send_update(const char *entry, bool finish_line);
+
+/**
+ * Clears all text entries and refreshes the display to white.
+ */
+void epaper_clear();
+
+/**
+ * Forces a full refresh of the display on the next update.
+ * Useful for clearing ghosting.
+ */
+void epaper_force_refresh();
+
+#endif // EPAPER_MANAGER_H

hello_usb.c

@@ -1,135 +0,0 @@
-/**
- * Simple USB Serial Echo Program with Timeout, Reconnect, and Backspace Logic.
- * This program now correctly handles the backspace character by deleting it 
- * from the buffer and sending the necessary control codes to the terminal 
- * for visual deletion.
- */
-
-#include "pico/stdlib.h"
-#include "pico/time.h" // Needed for time_us_64()
-#include <stdio.h>
-#include <ctype.h>
-
-// Define the maximum size for the input string buffer
-#define MAX_INPUT_LEN 64
-// Define the timeout period: 1 second in microseconds
-#define TIMEOUT_US 5000000
-// ASCII code for Backspace (often sent as 0x08)
-#define ASCII_BACKSPACE 8
-
-// Helper function to handle the echoing and resetting of the buffer
-void echo_and_reset(char* buffer, int* index_ptr) {
-    if (*index_ptr > 0) {
-        // Null-terminate the string
-        buffer[*index_ptr] = '\0';
-        
-        // Echo the string back, converting to uppercase
-        printf("\nEchoed (ALL CAPS): ");
-        for (int i = 0; buffer[i] != '\0'; i++) {
-            printf("%c", toupper(buffer[i]));
-        }
-        printf("\n");
-    }
-    
-    // Reset buffer for next line and print a new prompt
-    *index_ptr = 0;
-    printf("> ");
-}
-
-// Function to handle the initial waiting and reconnect waiting
-void wait_for_usb_connection() {
-    printf("Waiting for USB host to connect...\n");
-    // Wait until the USB host (e.g., terminal program) opens the serial port
-    while (!stdio_usb_connected()) {
-        sleep_ms(100);
-    }
-    // Connection established!
-    printf("\nConnection Established! Starting Echo Session...\n");
-}
-
-void run_echo_session() {
-    char input_buffer[MAX_INPUT_LEN];
-    int buffer_index = 0;
-    // Track the time (in microseconds) when the last character was received
-    uint64_t last_char_time = time_us_64();
-    
-    printf("--- Pico USB String Echo Program Started ---\n");
-    printf("Type a sentence (up to %d chars). It will echo on Enter/Timeout.\n", MAX_INPUT_LEN - 2);
-    printf("--------------------------------------------\n");
-    printf("> "); // Prompt for input
-
-    // Inner loop runs ONLY while the USB connection is active
-    while (stdio_usb_connected()) {
-        
-        // Check for incoming character without blocking
-        int c = getchar_timeout_us(0); 
-
-        if (c != PICO_ERROR_TIMEOUT) {
-            
-            // Character received, update the timer
-            last_char_time = time_us_64();
-            char input_char = (char)c;
-
-            // 1. --- BACKSPACE HANDLING ---
-            if (input_char == ASCII_BACKSPACE || input_char == 127) { // 127 is sometimes sent by terminals (DEL key)
-                if (buffer_index > 0) {
-                    // Decrease buffer index (remove the character)
-                    buffer_index--; 
-                    // Send backspace, space, and backspace to erase the character on the terminal:
-                    // \b: move cursor back
-                    // ' ': overwrite with a space
-                    // \b: move cursor back again, ready for the next character
-                    printf("\b \b"); 
-                }
-            // 2. --- End of Input (Newline/CR) ---
-            } else if (input_char == '\r' || input_char == '\n') {
-                echo_and_reset(input_buffer, &buffer_index);
-            
-            // 3. --- Collect regular characters ---
-            } else if (buffer_index < (MAX_INPUT_LEN - 1) && isprint(input_char)) {
-                
-                // Echo character locally so the user sees what they type
-                printf("%c", input_char);
-                
-                // Store character in the buffer
-                input_buffer[buffer_index] = input_char;
-                buffer_index++;
-            }
-            // Ignore non-printable characters and overflowed buffer input
-        }
-        
-        // 4. Timeout Check 
-        if (buffer_index > 0 && (time_us_64() - last_char_time) > TIMEOUT_US) {
-            printf("\n--- Timeout Reached (5.0s silence) ---\n");
-            echo_and_reset(input_buffer, &buffer_index);
-            last_char_time = time_us_64(); // Reset time to prevent immediate re-trigger
-        }
-        
-        // Add a small delay to prevent the loop from consuming too much CPU time
-        sleep_us(100); 
-    }
-
-    // Connection lost or closed by host
-    printf("\nHost disconnected. Ending Echo Session.\n");
-}
-
-
-int main() {
-    // Initialize Standard I/O (stdio) to use the USB backend
-    stdio_init_all();
-    
-    // Outer loop: Allows the program to run continuously and restart the
-    // session after a disconnection.
-    while (true) {
-        
-        // 1. Wait for a connection
-        wait_for_usb_connection();
-
-        // 2. Run the program logic while connected
-        run_echo_session();
-        
-        // Loop repeats, going back to wait_for_usb_connection()
-    }
-
-    // Note: main should not return
-}

hello_usb.cpp

@@ -1,329 +1,251 @@
 /*
- * Simple USB Serial Echo Program with Timeout, Reconnect, and Backspace Logic.
- * Converted to C++ so the project can use the `pico-ssd1306` C++ library.
- * Integrated with e-ink display support via Pico_ePaper library.
+ * USB Host Keyboard Example with Display Support
  */
 
 #include "pico/stdlib.h"
-#include "pico/time.h" // Needed for time_us_64()
+#include "pico/time.h"
 #include "pico/multicore.h"
+#include "tusb.h"
 #include <stdio.h>
 #include <ctype.h>
 #include <cstring>
 #include <stdlib.h>
+#include <malloc.h>
 
 #include "display.h"
 #include "commands/echo.h"
-
-// e-Paper library includes
-extern "C" {
-    #include "DEV_Config.h"
-    #include "EPD_7in5b_V2.h"
-    #include "GUI_Paint.h"
-}
+#include "keyboard_input.h"
+#include "command_processor.h"
+#include "epaper_manager.h"
+#include "wifi_manager.h"
 
 // Holds last echoed line for display
 static char g_last_echo[128] = "";
 
-// e-Paper display buffers
-static UBYTE *g_epd_image = NULL;  // Black image buffer
-static UBYTE *g_epd_red = NULL;    // Red image buffer
+// Global DisplayManager pointer
+static DisplayManager* g_display_manager = nullptr;
 
-// Entry list for display
-#define MAX_ENTRIES 15
-#define ENTRY_LENGTH 64
-typedef struct {
-    char entries[MAX_ENTRIES][ENTRY_LENGTH];
-    int count;
-} EntryList;
-static EntryList g_entry_list = {{}, 0};
-static bool g_force_full_refresh = false;  // Flag to force full refresh when list is full
-
-// Synchronization flag for multicore initialization
-static volatile bool g_display_ready = false;
-
-// Display update message structure for inter-core communication
-typedef struct {
-    EntryList entries;
-    bool use_partial;  // Use partial refresh instead of full refresh
-    UWORD xstart;      // Partial refresh region
-    UWORD ystart;
-    UWORD xend;
-    UWORD yend;
-} DisplayMessage;
-
-void init_epaper_display() {
-    printf("Initializing 7.5\" e-Paper display (B V2)...\r\n");
-    
-    // Initialize the hardware
-    if (DEV_Module_Init() != 0) {
-        printf("Failed to initialize e-Paper hardware!\r\n");
-        return;
-    }
-    
-    // Initialize the display
-    printf("EPD_7IN5B_V2_Init()\r\n");
-    EPD_7IN5B_V2_Init_Fast();
-    printf("EPD_7IN5B_V2_Clear()\r\n");
-    EPD_7IN5B_V2_Clear();
-    DEV_Delay_ms(500);
-    
-    // Create image buffers for black and red content
-    // 7.5" display: 800x480, 8 pixels per byte, so (800/8) * 480 = 48000 bytes each
-    UWORD imagesize = (EPD_7IN5B_V2_WIDTH / 8) * EPD_7IN5B_V2_HEIGHT;
-    
-    g_epd_image = (UBYTE *)malloc(imagesize);
-    g_epd_red = (UBYTE *)malloc(imagesize);
-    
-    if (g_epd_image == NULL || g_epd_red == NULL) {
-        printf("Failed to allocate memory for e-Paper image buffers!\r\n");
-        return;
-    }
-    
-    // Initialize red buffer to all white (0xFF = no red pixels)
-    for (UWORD i = 0; i < imagesize; i++) {
-        g_epd_red[i] = 0xFF;
-    }
-    
-    // Setup paint buffer for black content
-    printf("White background\r\n");
-    Paint_NewImage(g_epd_image, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT, 0, WHITE);
-    Paint_SelectImage(g_epd_image);
-    Paint_Clear(WHITE);
-    
-    // Draw header
-    EPD_7IN5B_V2_Init_Part();
-    Paint_SelectImage(g_epd_red);
-    printf("Drawing header\r\n");
-    Paint_DrawString_EN(10, 10, "What's new today:", &Font24, WHITE, RED);
-    
-    // Display the image with both black and red buffers
-    // printf("display text\r\n");
-    EPD_7IN5B_V2_Display_Partial(g_epd_red, 0, 0, EPD_7IN5B_V2_WIDTH, EPD_7IN5B_V2_HEIGHT);
-    // printf("delay\r\n");
-    // DEV_Delay_ms(1000);
-    
-    printf("e-Paper display ready!\r\n");
-    // EPD_7IN5B_V2_Sleep();
-}
-
-// Define the maximum size for the input string buffer
+// Keyboard buffer
 #define MAX_INPUT_LEN 64
-// Define the timeout period: 5 seconds in microseconds
-#define TIMEOUT_US 5000000
-// ASCII code for Backspace (often sent as 0x08)
-#define ASCII_BACKSPACE 8
+static char g_input_buffer[MAX_INPUT_LEN];
+static int g_buffer_index = 0;
 
-/**
- * Add an entry to the display list and send update to core 1
- */
-void send_display_update(const char *entry) {
-    if (!g_display_ready) return;  // Don't send if display isn't ready
-    
-    // Check if list is at capacity
-    if (g_entry_list.count >= MAX_ENTRIES) {
-        // List is full - clear all entries and start fresh
-        printf("[Core 0] List is FULL - clearing all entries and starting fresh\n");
-        g_entry_list.count = 0;
-        g_force_full_refresh = true;
-    }
-    
-    // Add entry to global list
-    strncpy(g_entry_list.entries[g_entry_list.count], entry, ENTRY_LENGTH - 1);
-    g_entry_list.entries[g_entry_list.count][ENTRY_LENGTH - 1] = '\0';
-    g_entry_list.count++;
-    
-    // Allocate message structure
-    DisplayMessage *msg = (DisplayMessage *)malloc(sizeof(DisplayMessage));
-    if (msg == NULL) {
-        printf("Failed to allocate display message!\n");
-        return;
-    }
-    
-    // Copy entry list to message
-    msg->entries = g_entry_list;
-    
-    // Decide whether to use partial or full refresh
-    msg->use_partial = !g_force_full_refresh;
-    
-    if (g_force_full_refresh) {
-        printf("[Core 0] Forcing full refresh this update\n");
-        g_force_full_refresh = false;  // Reset flag after setting it in message
-    }
-    
-    // Setup partial refresh region (text area at top of display)
-    msg->xstart = 0;
-    msg->ystart = 50;      // Start below the header
-    msg->xend = 800;       // Full width
-    msg->yend = 480;       // Full height from header onwards
-    
-    // Send message pointer to core 1
-    multicore_fifo_push_blocking((uint32_t)msg);
-    
-    // Wait for core 1 to complete the update
-    multicore_fifo_pop_blocking();
-}
-
-/**
- * Core 1 function: Runs display initialization and update handling
- */
-void core1_display_init() {
-    init_epaper_display();
-    g_display_ready = true;
-    
-    printf("[Core 1] Display ready, waiting for update messages...\n");
-    
-    // Initialize for partial refresh on second call
-    EPD_7IN5B_V2_Init_Part();
-    
-    // Core 1 main loop: handle display updates via FIFO
-    while (true) {
-        // Check if there's a message from core 0
-        if (multicore_fifo_rvalid()) {
-            // Read the message pointer
-            uint32_t msg_addr = multicore_fifo_pop_blocking();
-            DisplayMessage *msg = (DisplayMessage *)msg_addr;
+static bool execute_command(CommandAction action, const char* input) {
+    switch (action) {
+        case CMD_REFRESH:
+            printf("Command: /refresh\n");
+            epaper_force_refresh();
+            return true;
+        case CMD_CLEAR:
+            printf("Command: /clear\n");
+            epaper_clear();
+            return true;
+        case CMD_SCAN:
+            printf("Command: /scan\n");
+            if (g_display_manager) g_display_manager->refresh("Scanning WiFi...", nullptr);
+            epaper_send_update("Scanning WiFi...", true);
+            wifi_scan();
+            return true;
+        case CMD_CONNECT: {
+            printf("Command: /connect\n");
+            char ssid[33] = {0};
+            char password[64] = {0};
+            // Skip "/connect " (9 chars)
+            const char* args = input + 9;
             
-            printf("[Core 1] Updating display with %d entries\n", msg->entries.count);
-            
-            // Update the e-Paper display
-            if (g_epd_image != NULL && g_epd_red != NULL) {
-                UWORD imagesize = (EPD_7IN5B_V2_WIDTH / 8) * EPD_7IN5B_V2_HEIGHT;
-                
-                // For partial refresh, only clear the text area
-                UWORD width = (EPD_7IN5B_V2_WIDTH / 8);
-                UWORD y_start = msg->ystart;
-                UWORD y_end = msg->yend;
-                
-                Paint_SelectImage(g_epd_image);
-                Paint_Clear(WHITE);
-                if(!msg->use_partial){
-                    // for loop 5 times display white partial
-                    int i = 0;
-                    for(i = 0; i < 1; i++){
-                        EPD_7IN5B_V2_Display_Partial(g_epd_image, msg->xstart, msg->ystart, msg->xend, msg->yend);
-                    }
-                }
-                
-                // Draw all entries starting below header
-                UWORD y_pos = 0;
-                /*for (int i = 0; i < msg->entries.count; i++) {
-                    if (y_pos + 20 < 480) {  // Don't draw beyond screen
-                        Paint_DrawString_EN(20, y_pos, msg->entries.entries[i], &Font16, WHITE, BLACK);
-                        y_pos += 25;  // Space between entries
-                    }
-                }*/
-                // paint only the last 3 entries
-                int start_index = msg->entries.count > 2 ? msg->entries.count - 2 : 0;
-                for (int i = start_index; i < msg->entries.count; i++) {
-                    if (y_pos + 25 < 480) {  //Don't draw beyond screen
-                        Paint_DrawString_EN(20, i*25, msg->entries.entries[i], &Font16, WHITE, BLACK);
-                        y_pos += 25;  // Space between entries
-                    } else {
-                        printf("Skipping entry to avoid overflow\n");
-                    }
-                }
-                // Use partial or full refresh
-                //if (msg->use_partial) {
-                    printf("[Core 1] Using partial refresh\n");
-                    EPD_7IN5B_V2_Display_Partial(g_epd_image, msg->xstart, msg->ystart, msg->xend, msg->yend);
-                /*} else {
-                    printf("[Core 1] Using full refresh\n");
-                    // EPD_7IN5B_V2_Init();
-                    // EPD_7IN5B_V2_Clear();
-                    // DEV_Delay_ms(500);
-                    
-                    // Re-initialize partial refresh mode after full refresh
-                    printf("[Core 1] Reinitializing partial refresh mode\n");
-                    EPD_7IN5B_V2_Init_Part();
-                    Paint_SelectImage(g_epd_image);
-                    EPD_7IN5B_V2_Display_Partial(g_epd_image, msg->xstart, msg->ystart, msg->xend, msg->yend);
-                }*/
+            // Simple parsing: first word is ssid, rest is password
+            int parsed = sscanf(args, "%32s %63s", ssid, password);
+            if (parsed < 2) {
+                printf("Usage: /connect <ssid> <password>\n");
+                if (g_display_manager) g_display_manager->refresh("Usage: /connect <ssid> <pass>", nullptr);
+                epaper_send_update("Usage: /connect <ssid> <pass>", true);
+                return true;
             }
             
-            // Free the message (it was allocated by core 0)
-            free(msg);
+            if (g_display_manager) g_display_manager->refresh("Connecting...", ssid);
+            // epaper_send_update("Connecting...", true);
             
-            // Signal back to core 0 that update is complete
-            multicore_fifo_push_blocking(1);
+            if (wifi_connect(ssid, password)) {
+                if (g_display_manager) g_display_manager->refresh("Connected!", ssid);
+                int rc = wifi_save_credentials(ssid, password);
+                if (rc != 0) {
+                    char err_msg[32];
+                    snprintf(err_msg, sizeof(err_msg), "Flash Error: %d", rc);
+                    if (g_display_manager) g_display_manager->refresh(err_msg, nullptr);
+                    epaper_send_update(err_msg, true);
+                } else {
+                    epaper_send_update("Connected!", true);
+                }
+            } else {
+                if (g_display_manager) g_display_manager->refresh("Connection Failed", nullptr);
+                epaper_send_update("Connection Failed", true);
+            }
+            return true;
         }
-        
-        sleep_ms(10);
+        case CMD_STATUS: {
+            printf("Command: /status\n");
+            struct mallinfo m = mallinfo();
+            char status_msg[64];
+            // fordblks is the free chunk size in the arena. 
+            // Note: This might not account for the total available system RAM if the heap hasn't grown to fill it yet.
+            // But it gives an idea of fragmentation and available malloc-able memory within the current arena.
+            snprintf(status_msg, sizeof(status_msg), "Heap: %d B, IP: %s", m.fordblks, wifi_get_ip());
+            printf("%s\n", status_msg);
+            if (g_display_manager) g_display_manager->refresh(status_msg, nullptr);
+            epaper_send_update(status_msg, true);
+            return true;
+        }
+        default:
+            return false;
     }
 }
 
-void wait_for_usb_connection(DisplayManager &display) {
-    printf("Waiting for USB host to connect...\n");
-    while (!stdio_usb_connected()) {
-        sleep_ms(100);
-    }
-    printf("\nConnection Established! Starting Echo Session...\n");
-    display.refresh(">", nullptr);
-}
-
-void run_echo_session(DisplayManager &display) {
-    char input_buffer[MAX_INPUT_LEN];
-    int buffer_index = 0;
-
-    printf("--- Welcome User! ---\n");
-    printf("Type a command (or write help):\n");
-    printf("--------------------------------------------\n");
-    printf("> ");
-
-    while (stdio_usb_connected()) {
-        int c = getchar_timeout_us(0);
-        if (c != PICO_ERROR_TIMEOUT) {
-            char input_char = (char)c;
-            if (input_char == ASCII_BACKSPACE || input_char == 127) {
-                if (buffer_index > 0) {
-                    buffer_index--;
-                    printf("\b \b");
-                    // update displays to reflect removed char
-                    input_buffer[buffer_index] = '\0';
-                    display.refresh(input_buffer, g_last_echo);
-                    // send_display_update(input_buffer, g_last_echo);
+static void process_kbd_report(hid_keyboard_report_t const *report) {
+    KeyEvent event;
+    if (parse_keyboard_report(report, &event)) {
+        if (event.is_backspace) {
+            if (g_buffer_index > 0) {
+                printf("\b \b");
+                g_buffer_index--;
+                g_input_buffer[g_buffer_index] = '\0';
+                
+                // Update OLED
+                if (g_display_manager) g_display_manager->refresh(g_input_buffer, g_last_echo);
+                
+                // Update e-Paper (in-place)
+                epaper_send_update(g_input_buffer, false);
+            }
+        } else if (event.is_enter) {
+            printf("\n");
+            
+            // Always commit the input line to e-Paper so commands are visible
+            if (g_buffer_index > 0) {
+                epaper_send_update(g_input_buffer, true);
+            }
+            
+            CommandAction action = parse_command(g_input_buffer);
+            if (execute_command(action, g_input_buffer)) {
+                // Command handled
+                if (g_display_manager) {
+                    g_display_manager->set_last_echo("Command Executed");
+                    g_display_manager->refresh("", "Command Executed");
                 }
-            } else if (input_char == '\r' || input_char == '\n') {
-                echo_and_reset(input_buffer, &buffer_index);
-                // Save last echoed (all caps) for display
-                size_t i = 0;
-                for (; input_buffer[i] != '\0' && i < sizeof(g_last_echo) - 1; ++i) {
-                    g_last_echo[i] = input_buffer[i];
+            } else {
+                // Not a command, just text (already committed to e-Paper above)
+                
+                // Save to last echo
+                strncpy(g_last_echo, g_input_buffer, sizeof(g_last_echo) - 1);
+                g_last_echo[sizeof(g_last_echo) - 1] = '\0';
+                
+                // Update OLED
+                if (g_display_manager) {
+                    g_display_manager->set_last_echo(g_last_echo);
+                    g_display_manager->refresh("", g_last_echo);
                 }
-                g_last_echo[i] = '\0';
-                // Update both displays to show cleared input and last echo
-                display.set_last_echo(g_last_echo);
-                display.refresh("", g_last_echo);
-                send_display_update(g_last_echo);
-            } else if (buffer_index < (MAX_INPUT_LEN - 1) && isprint(input_char)) {
-                printf("%c", input_char);
-                input_buffer[buffer_index] = input_char;
-                buffer_index++;
-                // update both displays with current input
-                input_buffer[buffer_index] = '\0';
-                display.refresh(input_buffer, g_last_echo);
-                // send_display_update(input_buffer, g_last_echo);
+            }
+            
+            // Clear buffer
+            g_buffer_index = 0;
+            g_input_buffer[0] = '\0';
+        } else if (event.is_printable) {
+            printf("%c", event.ascii);
+            if (g_buffer_index < MAX_INPUT_LEN - 1) {
+                g_input_buffer[g_buffer_index++] = event.ascii;
+                g_input_buffer[g_buffer_index] = '\0';
+                
+                // Update OLED
+                if (g_display_manager) g_display_manager->refresh(g_input_buffer, g_last_echo);
+                
+                // Update e-Paper on every keystroke
+                epaper_send_update(g_input_buffer, false);
             }
         }
-        sleep_us(100);
     }
+}
+
+//--------------------------------------------------------------------+
+// TinyUSB Callbacks
+//--------------------------------------------------------------------+
+
+static bool g_keyboard_mounted = false;
+
+// Invoked when device is suspended
+void tuh_device_suspend_cb(uint8_t dev_addr) {
+    printf("Device address = %d suspended\r\n", dev_addr);
+}
+
+// Invoked when device is resumed
+void tuh_device_resume_cb(uint8_t dev_addr) {
+    printf("Device address = %d resumed\r\n", dev_addr);
+}
+
+void tuh_hid_mount_cb(uint8_t dev_addr, uint8_t instance, uint8_t const* desc_report, uint16_t desc_len) {
+    printf("HID device address = %d, instance = %d is mounted\r\n", dev_addr, instance);
+
+    uint8_t const itf_protocol = tuh_hid_interface_protocol(dev_addr, instance);
+    if (itf_protocol == HID_ITF_PROTOCOL_KEYBOARD) {
+        printf("Keyboard mounted\r\n");
+        g_keyboard_mounted = true;
+        if (g_display_manager) {
+            g_display_manager->refresh("Keyboard Connected", nullptr);
+        }
+        if (!tuh_hid_receive_report(dev_addr, instance)) {
+            printf("Error: cannot request to receive report\r\n");
+        }
+    }
+}
+
+void tuh_hid_umount_cb(uint8_t dev_addr, uint8_t instance) {
+    printf("HID device address = %d, instance = %d is unmounted\r\n", dev_addr, instance);
+    g_keyboard_mounted = false;
     
-    printf("\nHost disconnected. Ending Echo Session.\n");
+    // Reset input buffer
+    g_buffer_index = 0;
+    g_input_buffer[0] = '\0';
+
+    if (g_display_manager) {
+        g_display_manager->refresh("Waiting for Keyboard", nullptr);
+    }
+}
+
+void tuh_hid_report_received_cb(uint8_t dev_addr, uint8_t instance, uint8_t const* report, uint16_t len) {
+    uint8_t const itf_protocol = tuh_hid_interface_protocol(dev_addr, instance);
+
+    if (itf_protocol == HID_ITF_PROTOCOL_KEYBOARD) {
+        process_kbd_report((hid_keyboard_report_t const*) report);
+    }
+
+    // continue to request to receive report
+    if (!tuh_hid_receive_report(dev_addr, instance)) {
+        printf("Error: cannot request to receive report\r\n");
+    }
 }
 
 int main() {
     stdio_init_all();
-    // Launch display initialization on core 1
-    printf("Launching e-Paper display init on core 1...\n");
-    multicore_launch_core1(core1_display_init);
+    sleep_ms(3000); // Give time for power to settle and serial to connect
+    printf("System Booting...\n");
+    
+    // Launch display initialization on core 1, WIFI and Flash safe execute
+    epaper_start_background_thread();
     
     DisplayManager display;
     display.init();
-    display.refresh("Waiting for USB/Serial", nullptr);
+    g_display_manager = &display;
+    
+    printf("Initializing TinyUSB Host...\n");
+    tuh_init(BOARD_TUH_RHPORT);
+    printf("TinyUSB Host Initialized.\n");
 
+    uint32_t last_print = 0;
     while (true) {
-        wait_for_usb_connection(display);
-        run_echo_session(display);
+        tuh_task();
+        
+        uint32_t now = to_ms_since_boot(get_absolute_time());
+        if (now - last_print > 5000) {
+            printf("Heartbeat: %u, Mounted: %d\n", now, g_keyboard_mounted);
+            last_print = now;
+        }
     }
 
     return 0;

keyboard_input.cpp

@@ -0,0 +1,142 @@
+#include "keyboard_input.h"
+#include <stdio.h>
+
+static const uint8_t keycode2ascii[128][2] =  {
+    {0, 0}, /* 0x00 */
+    {0, 0}, /* 0x01 */
+    {0, 0}, /* 0x02 */
+    {0, 0}, /* 0x03 */
+    {'a', 'A'}, /* 0x04 */
+    {'b', 'B'}, /* 0x05 */
+    {'c', 'C'}, /* 0x06 */
+    {'d', 'D'}, /* 0x07 */
+    {'e', 'E'}, /* 0x08 */
+    {'f', 'F'}, /* 0x09 */
+    {'g', 'G'}, /* 0x0a */
+    {'h', 'H'}, /* 0x0b */
+    {'i', 'I'}, /* 0x0c */
+    {'j', 'J'}, /* 0x0d */
+    {'k', 'K'}, /* 0x0e */
+    {'l', 'L'}, /* 0x0f */
+    {'m', 'M'}, /* 0x10 */
+    {'n', 'N'}, /* 0x11 */
+    {'o', 'O'}, /* 0x12 */
+    {'p', 'P'}, /* 0x13 */
+    {'q', 'Q'}, /* 0x14 */
+    {'r', 'R'}, /* 0x15 */
+    {'s', 'S'}, /* 0x16 */
+    {'t', 'T'}, /* 0x17 */
+    {'u', 'U'}, /* 0x18 */
+    {'v', 'V'}, /* 0x19 */
+    {'w', 'W'}, /* 0x1a */
+    {'x', 'X'}, /* 0x1b */
+    {'y', 'Y'}, /* 0x1c */
+    {'z', 'Z'}, /* 0x1d */
+    {'1', '!'}, /* 0x1e */
+    {'2', '@'}, /* 0x1f */
+    {'3', '#'}, /* 0x20 */
+    {'4', '$'}, /* 0x21 */
+    {'5', '%'}, /* 0x22 */
+    {'6', '^'}, /* 0x23 */
+    {'7', '&'}, /* 0x24 */
+    {'8', '*'}, /* 0x25 */
+    {'9', '('}, /* 0x26 */
+    {'0', ')'}, /* 0x27 */
+    {'\r', '\r'}, /* 0x28 ENTER */
+    {'\x1b', '\x1b'}, /* 0x29 ESCAPE */
+    {'\b', '\b'}, /* 0x2a BACKSPACE */
+    {'\t', '\t'}, /* 0x2b TAB */
+    {' ', ' '}, /* 0x2c SPACE */
+    {'-', '_'}, /* 0x2d MINUS */
+    {'=', '+'}, /* 0x2e EQUAL */
+    {'[', '{'}, /* 0x2f BRACKET_LEFT */
+    {']', '}'}, /* 0x30 BRACKET_RIGHT */
+    {'\\', '|'}, /* 0x31 BACKSLASH */
+    {'#', '~'}, /* 0x32 EUROPE_1 */
+    {';', ':'}, /* 0x33 SEMICOLON */
+    {'\'', '\"'}, /* 0x34 APOSTROPHE */
+    {'`', '~'}, /* 0x35 GRAVE */
+    {',', '<'}, /* 0x36 COMMA */
+    {'.', '>'}, /* 0x37 PERIOD */
+    {'/', '?'}, /* 0x38 SLASH */
+    {0, 0}, /* 0x39 CAPS_LOCK */
+    {0, 0}, /* 0x3a F1 */
+    {0, 0}, /* 0x3b F2 */
+    {0, 0}, /* 0x3c F3 */
+    {0, 0}, /* 0x3d F4 */
+    {0, 0}, /* 0x3e F5 */
+    {0, 0}, /* 0x3f F6 */
+    {0, 0}, /* 0x40 F7 */
+    {0, 0}, /* 0x41 F8 */
+    {0, 0}, /* 0x42 F9 */
+    {0, 0}, /* 0x43 F10 */
+    {0, 0}, /* 0x44 F11 */
+    {0, 0}, /* 0x45 F12 */
+    {0, 0}, /* 0x46 PRINT_SCREEN */
+    {0, 0}, /* 0x47 SCROLL_LOCK */
+    {0, 0}, /* 0x48 PAUSE */
+    {0, 0}, /* 0x49 INSERT */
+    {0, 0}, /* 0x4a HOME */
+    {0, 0}, /* 0x4b PAGE_UP */
+    {0, 0}, /* 0x4c DELETE */
+    {0, 0}, /* 0x4d END */
+    {0, 0}, /* 0x4e PAGE_DOWN */
+    {0, 0}, /* 0x4f RIGHT_ARROW */
+    {0, 0}, /* 0x50 LEFT_ARROW */
+    {0, 0}, /* 0x51 DOWN_ARROW */
+    {0, 0}, /* 0x52 UP_ARROW */
+    {0, 0}, /* 0x53 NUM_LOCK */
+    {'/', '/'}, /* 0x54 KP_DIVIDE */
+    {'*', '*'}, /* 0x55 KP_MULTIPLY */
+    {'-', '-'}, /* 0x56 KP_MINUS */
+    {'+', '+'}, /* 0x57 KP_PLUS */
+    {'\r', '\r'}, /* 0x58 KP_ENTER */
+    {'1', '1'}, /* 0x59 KP_1 */
+    {'2', '2'}, /* 0x5a KP_2 */
+    {'3', '3'}, /* 0x5b KP_3 */
+    {'4', '4'}, /* 0x5c KP_4 */
+    {'5', '5'}, /* 0x5d KP_5 */
+    {'6', '6'}, /* 0x5e KP_6 */
+    {'7', '7'}, /* 0x5f KP_7 */
+    {'8', '8'}, /* 0x60 KP_8 */
+    {'9', '9'}, /* 0x61 KP_9 */
+    {'0', '0'}, /* 0x62 KP_0 */
+    {'.', '.'}, /* 0x63 KP_DECIMAL */
+};
+
+static inline bool find_key_in_report(hid_keyboard_report_t const *report, uint8_t keycode) {
+    for(uint8_t i=0; i<6; i++) {
+        if (report->keycode[i] == keycode) return true;
+    }
+    return false;
+}
+
+bool parse_keyboard_report(hid_keyboard_report_t const *report, KeyEvent* result) {
+    static hid_keyboard_report_t prev_report = { 0, 0, {0} };
+    bool event_found = false;
+
+    for(uint8_t i=0; i<6; i++) {
+        if (report->keycode[i]) {
+            if (find_key_in_report(&prev_report, report->keycode[i])) {
+                // exist in previous report means the current key is holding
+            } else {
+                // not existed in previous report means the current key is pressed
+                bool const is_shift = report->modifier & (KEYBOARD_MODIFIER_LEFTSHIFT | KEYBOARD_MODIFIER_RIGHTSHIFT);
+                uint8_t ch = keycode2ascii[report->keycode[i]][is_shift ? 1 : 0];
+                
+                if (ch) {
+                    result->ascii = ch;
+                    result->is_enter = (ch == '\r' || ch == '\n');
+                    result->is_backspace = (ch == '\b' || ch == 127);
+                    result->is_printable = !result->is_enter && !result->is_backspace;
+                    event_found = true;
+                    // We only process one key event per report for simplicity in this refactor
+                    // Ideally we might want to queue them if multiple keys are pressed at once
+                    break; 
+                }
+            }
+        }
+    }
+    prev_report = *report;
+    return event_found;
+}

keyboard_input.h

@@ -0,0 +1,19 @@
+#ifndef KEYBOARD_INPUT_H
+#define KEYBOARD_INPUT_H
+
+#include "tusb.h"
+
+struct KeyEvent {
+    char ascii;
+    bool is_enter;
+    bool is_backspace;
+    bool is_printable;
+};
+
+/**
+ * Parses a raw HID keyboard report and returns true if a new key press was detected.
+ * The result is stored in the provided KeyEvent pointer.
+ */
+bool parse_keyboard_report(hid_keyboard_report_t const *report, KeyEvent* result);
+
+#endif // KEYBOARD_INPUT_H

lwipopts.h

@@ -0,0 +1,53 @@
+#ifndef _LWIPOPTS_H
+#define _LWIPOPTS_H
+
+// Common settings used in most of the pico_w examples
+#define NO_SYS                      1
+#define LWIP_SOCKET                 0
+
+#define MEM_LIBC_MALLOC             0
+
+#define MEM_ALIGNMENT               4
+#define MEM_SIZE                    4000
+#define MEMP_NUM_TCP_SEG            32
+#define MEMP_NUM_ARP_QUEUE          10
+#define PBUF_POOL_SIZE              24
+#define LWIP_ARP                    1
+#define LWIP_ETHERNET               1
+#define LWIP_ICMP                   1
+#define LWIP_RAW                    1
+#define TCP_WND                     (8 * TCP_MSS)
+#define TCP_MSS                     1460
+#define TCP_SND_BUF                 (8 * TCP_MSS)
+#define TCP_SND_QUEUELEN            ((4 * (TCP_SND_BUF) + (TCP_MSS - 1)) / (TCP_MSS))
+#define LWIP_NETIF_STATUS_CALLBACK  1
+#define LWIP_NETIF_LINK_CALLBACK    1
+#define LWIP_NETIF_HOSTNAME         1
+#define LWIP_NETCONN                0
+#define MEM_STATS                   0
+#define SYS_STATS                   0
+#define MEMP_STATS                  0
+#define LINK_STATS                  0
+#define LWIP_CHKSUM_ALGORITHM       3
+#define LWIP_DHCP                   1
+#define LWIP_IPV4                   1
+#define LWIP_TCP                    1
+#define LWIP_UDP                    1
+#define LWIP_DNS                    1
+#define LWIP_TCP_KEEPALIVE          1
+#define LWIP_NETIF_TX_SINGLE_PBUF   1
+#define DHCP_DOES_ARP_CHECK         0
+#define LWIP_DHCP_DOES_ACD_CHECK    0
+
+// Enable debugging
+#ifndef NDEBUG
+#define LWIP_DEBUG                  1
+#define LWIP_STATS                  1
+#define LWIP_PLATFORM_DIAG(x)       do {printf x;} while(0)
+#else
+#define LWIP_DEBUG                  0
+#define LWIP_STATS                  0
+#define LWIP_PLATFORM_DIAG(x)       do {} while(0)
+#endif
+
+#endif /* _LWIPOPTS_H */

suspend_fix_notes.md

@@ -0,0 +1,42 @@
+# TinyUSB Host Keyboard Suspend/Freeze Issues on RP2040
+
+## Common Issues
+1. **Device Auto-Suspend:** Some keyboards automatically enter a low-power suspend mode if they don't detect activity or if the host stops sending Start-Of-Frame (SOF) packets.
+2. **Host Controller Freeze:** The RP2040 USB host controller can sometimes get into a state where it stops processing events, especially if there are signal integrity issues or if the `tuh_task()` is blocked for too long.
+3. **Missing Keep-Alive:** If the host doesn't send SOFs, the device will suspend. The RP2040 host should send SOFs automatically when configured as host.
+
+## `tuh_task` Usage
+- **Requirement:** `tuh_task()` must be called continuously and frequently in the main loop.
+- **Blocking:** It should not be blocked by long delays (like `sleep_ms` or blocking display updates) in the same thread.
+- **Current Code:** Your `hello_usb.cpp` calls `tuh_task()` in a tight loop, which is correct. The display updates are offloaded to Core 1, and the FIFO push is non-blocking (checked with `multicore_fifo_wready`), so Core 0 should remain responsive.
+
+## Potential Fixes & Debugging
+
+### 1. Handle Suspend/Resume Callbacks
+TinyUSB provides callbacks to notify the application when a device suspends or resumes. Implementing these can help determine if the device is actually suspending.
+
+Add these to your `hello_usb.cpp`:
+
+```cpp
+// Invoked when device is suspended
+void tuh_device_suspend_cb(uint8_t dev_addr) {
+    printf("Device address = %d suspended\r\n", dev_addr);
+}
+
+// Invoked when device is resumed
+void tuh_device_resume_cb(uint8_t dev_addr) {
+    printf("Device address = %d resumed\r\n", dev_addr);
+}
+```
+
+### 2. Force Resume
+If the device suspends and doesn't wake up, you might need to force a resume from the host side, although usually the device initiates resume (remote wakeup) or the host keeps it awake.
+
+### 3. Check Power
+Ensure the keyboard is receiving sufficient power. Some mechanical keyboards with LEDs draw significant current, potentially causing voltage drops that reset the USB connection or cause a freeze.
+
+### 4. Disable Suspend (Device Side)
+Some devices have internal settings to disable sleep, but this is device-specific.
+
+### 5. SDK/TinyUSB Version
+Ensure you are using a recent version of the Pico SDK and TinyUSB, as there have been fixes for RP2040 host mode stability.

tusb_config.h

@@ -0,0 +1,46 @@
+#ifndef _TUSB_CONFIG_H_
+#define _TUSB_CONFIG_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//--------------------------------------------------------------------+
+// COMMON CONFIGURATION
+//--------------------------------------------------------------------+
+#define CFG_TUSB_MCU                OPT_MCU_RP2040
+
+// Host Mode
+#define CFG_TUH_ENABLED             1
+
+// RHPort number used for Host can be defined by board.mk, default to port 0
+#ifndef BOARD_TUH_RHPORT
+#define BOARD_TUH_RHPORT            0
+#endif
+
+// RHPort max operational speed can defined by board.mk
+#ifndef BOARD_TUH_MAX_SPEED
+#define BOARD_TUH_MAX_SPEED         OPT_MODE_DEFAULT_SPEED
+#endif
+
+//--------------------------------------------------------------------+
+// HOST CONFIGURATION
+//--------------------------------------------------------------------+
+
+// Size of buffer to hold descriptors and other data used for enumeration
+#define CFG_TUH_ENUMERATION_BUFSIZE 256
+
+#define CFG_TUH_HUB                 1
+#define CFG_TUH_CDC                 0
+#define CFG_TUH_HID                 4 // typical number of HID devices
+#define CFG_TUH_MSC                 0
+#define CFG_TUH_VENDOR              0
+
+// max device support (excluding hub device)
+#define CFG_TUH_DEVICE_MAX          (CFG_TUH_HUB ? 4 : 1) // hub typically has 4 ports
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _TUSB_CONFIG_H_ */

wifi_manager.cpp

@@ -0,0 +1,148 @@
+#include "wifi_manager.h"
+#include "pico/cyw43_arch.h"
+#include "pico/multicore.h"
+#include "pico/flash.h"
+#include "hardware/flash.h"
+#include "hardware/sync.h"
+#include <stdio.h>
+#include <string.h>
+
+// Use the last sector of the 2MB flash
+#define FLASH_TARGET_OFFSET (2 * 1024 * 1024 - FLASH_SECTOR_SIZE)
+#define WIFI_CREDS_MAGIC 0x42574946 // 'BWIF'
+
+struct WifiCreds {
+    uint32_t magic;
+    char ssid[33];
+    char password[64];
+};
+
+static volatile bool g_wifi_initialized = false;
+static bool g_wifi_connected = false;
+
+bool wifi_init() {
+    if (g_wifi_initialized) return true;
+
+    if (cyw43_arch_init()) {
+        printf("WiFi init failed!\n");
+        return false;
+    }
+
+    cyw43_arch_enable_sta_mode();
+    g_wifi_initialized = true;
+    printf("WiFi initialized on Core %u\n", get_core_num());
+    return true;
+}
+
+static int scan_result(void *env, const cyw43_ev_scan_result_t *result) {
+    if (result) {
+        printf("SSID: %-32s RSSI: %4d Auth: %u\n", result->ssid, result->rssi, result->auth_mode);
+    }
+    return 0;
+}
+
+void wifi_scan() {
+    // Wait for initialization
+    int timeout = 500; // 5 seconds
+    while (!g_wifi_initialized && timeout > 0) {
+        sleep_ms(10);
+        timeout--;
+    }
+
+    if (!g_wifi_initialized) {
+        printf("WiFi not initialized!\n");
+        return;
+    }
+    
+    printf("Starting WiFi scan...\n");
+    cyw43_wifi_scan_options_t scan_options = {0};
+    int err = cyw43_wifi_scan(&cyw43_state, &scan_options, NULL, scan_result);
+    if (err != 0) {
+        printf("Failed to start scan: %d\n", err);
+    }
+}
+
+// Helper struct for flash operations
+struct FlashWriteParams {
+    const uint8_t* data;
+    size_t size;
+};
+
+// Actual flash operation to be executed safely
+static void do_flash_write(void *param) {
+    FlashWriteParams *p = (FlashWriteParams*)param;
+    flash_range_erase(FLASH_TARGET_OFFSET, FLASH_SECTOR_SIZE);
+    flash_range_program(FLASH_TARGET_OFFSET, p->data, p->size);
+}
+
+int wifi_save_credentials(const char* ssid, const char* password) {
+    WifiCreds creds;
+    creds.magic = WIFI_CREDS_MAGIC;
+    strncpy(creds.ssid, ssid, sizeof(creds.ssid) - 1);
+    creds.ssid[sizeof(creds.ssid) - 1] = '\0';
+    strncpy(creds.password, password, sizeof(creds.password) - 1);
+    creds.password[sizeof(creds.password) - 1] = '\0';
+
+    FlashWriteParams params = { (const uint8_t*)&creds, sizeof(creds) };
+    int rc = flash_safe_execute(do_flash_write, &params, 1000);
+    
+    if (rc == PICO_OK) {
+        printf("WiFi credentials saved to flash.\n");
+    } else {
+        printf("Failed to save WiFi credentials: %d\n", rc);
+    }
+    return rc;
+}
+
+bool wifi_try_auto_connect() {
+    // On RP2040/RP2350, flash is memory-mapped at XIP_BASE (0x10000000).
+    // We can read from it directly like a normal pointer without special API calls.
+    // The hardware XIP controller handles fetching data from the flash chip.
+    const WifiCreds* creds = (const WifiCreds*)(XIP_BASE + FLASH_TARGET_OFFSET);
+    
+    // Check for the magic number to verify valid data exists.
+    // Erased flash reads as 0xFFFFFFFF, so this check fails if no data was saved.
+    if (creds->magic != WIFI_CREDS_MAGIC) {
+        printf("No saved WiFi credentials found.\n");
+        return false;
+    }
+    
+    printf("Found saved credentials for SSID: %s\n", creds->ssid);
+    return wifi_connect(creds->ssid, creds->password);
+}
+
+bool wifi_connect(const char* ssid, const char* password) {
+    // Wait for initialization
+    int timeout = 500; // 5 seconds
+    while (!g_wifi_initialized && timeout > 0) {
+        sleep_ms(10);
+        timeout--;
+    }
+
+    if (!g_wifi_initialized) {
+        printf("WiFi not initialized!\n");
+        return false;
+    }
+
+    printf("Connecting to WiFi: %s...\n", ssid);
+    
+    // Connect in blocking mode for simplicity
+    if (cyw43_arch_wifi_connect_timeout_ms(ssid, password, CYW43_AUTH_WPA2_AES_PSK, 30000)) {
+        printf("WiFi connection failed!\n");
+        g_wifi_connected = false;
+        return false;
+    }
+
+    printf("WiFi connected!\n");
+    g_wifi_connected = true;
+    return true;
+}
+
+bool wifi_is_connected() {
+    return g_wifi_connected;
+}
+
+const char* wifi_get_ip() {
+    if (!g_wifi_connected) return "Disconnected";
+    return ip4addr_ntoa(netif_ip4_addr(&cyw43_state.netif[0]));
+}

wifi_manager.h

@@ -0,0 +1,45 @@
+#ifndef WIFI_MANAGER_H
+#define WIFI_MANAGER_H
+
+#include <stdbool.h>
+
+/**
+ * Initializes the WiFi hardware.
+ * Returns true on success.
+ */
+bool wifi_init();
+
+/**
+ * Scans for available WiFi networks and prints them to stdout.
+ */
+void wifi_scan();
+
+/**
+ * Connects to the specified WiFi network.
+ * Returns true if connected successfully.
+ */
+bool wifi_connect(const char* ssid, const char* password);
+
+/**
+ * Saves the WiFi credentials to flash memory for auto-connect.
+ * Returns 0 (PICO_OK) on success, or an error code on failure.
+ */
+int wifi_save_credentials(const char* ssid, const char* password);
+
+/**
+ * Attempts to connect using saved credentials.
+ * Returns true if connected.
+ */
+bool wifi_try_auto_connect();
+
+/**
+ * Returns true if currently connected to WiFi.
+ */
+bool wifi_is_connected();
+
+/**
+ * Returns the current IP address as a string, or "Disconnected".
+ */
+const char* wifi_get_ip();
+
+#endif // WIFI_MANAGER_H