Valid SD pins for T3S3

PKA_SUMMARY.md

@@ -0,0 +1,24 @@
+---
+title: "esp32-debug-dongle"
+source: pka-assess
+---
+
+# esp32-debug-dongle
+
+## Purpose
+
+ESP32 dev-kit firmware turning the chip into a WiFi + Bluetooth serial-terminal dongle. Browser-based terminal uses xterm.js served from the ESP's LittleFS; also exposes a classic Bluetooth SPP port for desktop/mobile terminal apps. Multi-port (internal debug / USB / external Serial1) with on-the-fly baud-rate switching.
+
+## Type
+
+ESP32 PlatformIO firmware. `#embedded`, `#firmware`, `#iot`, `#service`.
+
+## Dependencies
+
+- **External:** PlatformIO `espressif32` + Arduino framework, xterm.js (bundled in LittleFS), Bluetooth SPP stack (classic BT — needs a WROOM-style ESP32, NOT S2/S3/C3).
+- **Internal:** complementary tool to ESP32 Sh3d projects — [[Sh3dNb]], [[Sh3dController]], [[Sh3dStick]], [[Doxy]] — when serial access is awkward.
+
+## Notable
+
+- Uses a `huge_app.csv` partition (3 MB app, 1 MB FS, no OTA) — swap to `min_spiffs.csv` if OTA is needed.
+- Classic Bluetooth requirement is a hard constraint on target hardware.

PLAN.md

@@ -0,0 +1,69 @@
+# esp32-debug-dongle → LilyGo T3-S3 debug bridge
+
+## Why
+USB serial to the trough/solartrack sensors drops on every deep sleep, so we
+can't watch boots/crashes/wakes. This dongle becomes an always-connected box on
+the LAN that bridges a sensor's UART to telnet + a web terminal, controls GPIO
+to reset/wake the target, logs to SD, and (Phase 2) sniffs the MeshCore LoRa
+mesh — so we can debug remotely and stop flying blind.
+
+## Decisions (confirmed with user)
+1. **Board: LilyGo T3-S3** (ESP32-S3 + SX127x LoRa + SSD1306 128×64 OLED + SD).
+   Chosen over TTGO for onboard SD and LoRa (mesh monitoring).
+2. **Extend `esp32-debug-dongle` in place** (not a new Sh3dNb app). Keep the
+   existing `esp32dev` env working; add a `t3s3` env.
+3. **Both telnet (:23) and the WebSocket terminal.** Telnet is the primary
+   remote control path (nc/minicom + an agent driving it); GPIO reset/wake and
+   port/baud are exposed as **both** telnet `~commands` and REST endpoints.
+4. **SD logging in Phase 1, ON by default** once NTP (built-in `configTzTime`)
+   gives today's date — log file named/stamped from real time.
+5. **Power monitoring: out of scope.**
+6. **Phase 2: MeshCore monitor** over the onboard LoRa (passive RX of mesh
+   packets, surfaced on telnet/web/SD).
+
+## Board facts that shape the build
+- ESP32-S3 has **no Bluetooth Classic** → `BluetoothSerial`/SerialBT is guarded
+  behind `HAS_BT_CLASSIC` (esp32dev only). On T3-S3, telnet + WebSocket replace it.
+- USB CDC on boot (`-DARDUINO_USB_CDC_ON_BOOT=1`) → UART0 (GPIO43/44) is free for
+  the target bridge.
+- Pins (from `Sh3dNb/apps_oglas/lilygot3s3_basic`): OLED SDA18/SCL17/RST21@0x3C;
+  LoRa SCK5/MISO3/MOSI6/CS7/RST8/DIO0:9; BTN0.
+
+## Phase 1 (this build) — extend src/main.cpp + platformio.ini
+- **platformio.ini**: keep `[env:esp32dev]` (+ `-DHAS_BT_CLASSIC=1`); add
+  `[env:t3s3]` (esp32-s3-devkitc-1, USB CDC on boot, huge_app, littlefs,
+  Adafruit SSD1306+GFX). All pins via build flags (target UART, GPIO reset/wake,
+  SD, OLED) so they're config, not hardcoded.
+- **Target UART bridge**: Serial1 on `TARGET_RX/TX` pins ↔ fan-out to WebSocket
+  (existing), **telnet clients**, and **SD log**. RX/TX byte+line counters.
+- **Telnet server :23** with line protocol: non-`~` lines forward to the target
+  UART; `~` lines are commands:
+  `~help ~status ~reset [ms] ~wake [ms] ~baud <n> ~port <int|usb|ext> ~log on|off
+   ~gpio <pin> <0|1>`. Lets an operator (or agent via `nc`) drive a remote board.
+- **REST** (mirror of the commands): `/api/status /api/reset /api/wake
+  /api/baud?baud= /api/log?on= /api/gpio?pin=&val= /api/send?data=`.
+- **GPIO control**: configurable `reset`/`wake` pins (active-low option), pulse.
+- **NTP + SD logging**: `configTzTime(<TZ>)`; once time syncs, open
+  `/logs/YYYYMMDD-HHMMSS.log` and append timestamped serial. Logging ON by
+  default; `~log off` / REST toggles. Graceful no-op if SD absent/pins wrong.
+- **OLED**: IP/SSID/RSSI, target pins+baud, RX/TX counts, telnet client count,
+  logging on/off, NTP synced y/n.
+
+## Phase 2 — MeshCore monitor (later)
+- Bring up the T3-S3 LoRa radio (confirm chip: SX1276 vs SX1262 variant) with
+  the mesh's PHY (freq/SF/BW/CR matching the sensors), RX-only.
+- Decode/forward MeshCore channel frames to telnet/web/SD so we see beacons
+  (e.g. count trough beacons to confirm the sleep-crash fix) without a sensor.
+
+## Pins to CONFIRM against the actual board (set as build flags)
+- **SD**: SCK/MISO/MOSI/CS for the T3-S3 SD slot (may share the LoRa SPI bus +
+  own CS — verify). Logging silently disables if wrong.
+- **Target UART bridge** RX/TX (default UART0 43/44, free under USB CDC).
+- **GPIO reset/wake** pins to whatever lines you wire to the sensor's RST/control.
+- **LoRa chip variant** (Phase 2).
+
+## Verify
+- `pio run -e t3s3` compiles; `pio run -e esp32dev` still compiles (BT intact).
+- Flash T3-S3: OLED shows IP; `nc <ip> 23` streams a wired sensor's UART;
+  `~reset` reboots it (seen on the same stream); a dated file appears under
+  `/logs` on the SD and grows.

README.md

@@ -9,7 +9,6 @@ A WiFi/Bluetooth serial debugging tool for ESP32. Access serial ports via web br
 - **Multi-Port**: Switch between internal debug, USB serial, and external serial
 - **Virtual Serial**: Internal loopback for ESP32's own debug output
 - **Configurable**: Change baud rates on the fly
-- **Robust Server**: Uses PsychicHttp - stable under load (unlike ESPAsyncWebServer)
 
 ## Hardware
 
@@ -54,19 +53,8 @@ pio run -t uploadfs
 
 ### 3. Connect
 
-#### Via WiFi (Station Mode - Default)
+#### Via WiFi (Web Terminal)
 
-1. Edit `src/main.cpp` and set your WiFi credentials:
-   ```cpp
-   const char* STA_SSID = "YourNetworkSSID";
-   const char* STA_PASSWORD = "YourPassword";
-   ```
-2. Upload and check serial monitor for the assigned IP address
-3. Open browser: `http://<ip-address>`
-
-#### Via WiFi (AP Mode Fallback)
-
-If station mode fails, or you set `WIFI_STATION_MODE false`:
 1. Connect to WiFi network: `ESP32-DebugDongle`
 2. Password: `debug1234`
 3. Open browser: `http://192.168.4.1`
@@ -118,20 +106,10 @@ These messages appear when "Internal" port is selected.
 Edit `src/main.cpp` to change defaults:
 
 ```cpp
-// WiFi Mode: true = connect to existing network, false = create AP
+// WiFi Access Point
-#define WIFI_STATION_MODE true
-
-// Your WiFi network credentials (station mode)
-const char* STA_SSID = "YourNetworkSSID";
-const char* STA_PASSWORD = "YourPassword";
-
-// Fallback Access Point settings
 const char* AP_SSID = "ESP32-DebugDongle";
 const char* AP_PASSWORD = "debug1234";
 
-// Connection timeout before falling back to AP mode
-#define WIFI_CONNECT_TIMEOUT 15000
-
 // Bluetooth name
 const char* BT_NAME = "ESP32-Debug";
 
@@ -144,18 +122,6 @@ const char* BT_NAME = "ESP32-Debug";
 #define DEFAULT_BAUD_SERIAL1 115200
 ```
 
-### WiFi Modes
-
-**Station Mode** (`WIFI_STATION_MODE true`):
-- Connects to your existing WiFi network
-- Access the dongle from any device on the same network
-- Falls back to AP mode if connection fails
-
-**Access Point Mode** (`WIFI_STATION_MODE false`):
-- Creates its own WiFi network
-- Connect directly to the ESP32's network
-- IP address: 192.168.4.1
-
 ## Project Structure
 
 ```
@@ -271,5 +237,5 @@ MIT License - Feel free to use and modify.
 ## Credits
 
 - [xterm.js](https://xtermjs.org/) - Terminal emulator
-- [PsychicHttp](https://github.com/hoeken/PsychicHttp) - Robust HTTP/WebSocket server for ESP32
+- [ESPAsyncWebServer](https://github.com/me-no-dev/ESPAsyncWebServer) - Async web server
 - [ArduinoJson](https://arduinojson.org/) - JSON library by Benoît Blanchon

data/index.html

@@ -167,6 +167,8 @@
             </div>
             <button onclick="clearTerminal()">Clear</button>
             <button onclick="reconnect()">Reconnect</button>
+            <button id="logBtn" onclick="toggleLog()">Log: --</button>
+            <button onclick="toggleFiles()">Files</button>
         </div>
         <div class="status">
             <div class="status-item">
@@ -184,6 +186,14 @@
         </div>
     </div>
     
+    <div id="filesPanel" style="display:none; background:#16213e; border-bottom:1px solid #0f3460; padding:10px 20px; max-height:40vh; overflow:auto;">
+        <div style="display:flex; justify-content:space-between; align-items:center; margin-bottom:8px;">
+            <strong>SD log files</strong>
+            <span><span id="logState" style="color:#aaa; margin-right:10px;"></span><button onclick="refreshLogs()">Refresh</button></span>
+        </div>
+        <table id="filesTable" style="width:100%; border-collapse:collapse; font-size:0.85em;"></table>
+    </div>
+
     <div class="terminal-container">
         <div id="terminal"></div>
     </div>
@@ -315,6 +325,7 @@
                     document.getElementById('baudSelect').value = msg.baudSerial1;
                     updateStatus('btStatus', msg.btConnected);
                     document.getElementById('heap').textContent = `Heap: ${msg.freeHeap}`;
+                    updateLogUi(msg);
                     
                     // Show WiFi info
                     const wifiInfo = document.getElementById('wifiInfo');
@@ -407,6 +418,52 @@
             return (bytes / 1024 / 1024).toFixed(1) + ' MB';
         }
 
+        // ---- SD logging controls ----
+        let logOn = false;
+        function toggleLog() {
+            fetch('/api/log?on=' + (logOn ? 0 : 1))
+                .then(r => r.json()).then(updateLogUi)
+                .catch(() => term.writeln('\r\n\x1b[31m[log toggle failed]\x1b[0m'));
+        }
+        function updateLogUi(s) {
+            if (typeof s.log === 'undefined') return;
+            logOn = !!s.log;
+            const b = document.getElementById('logBtn');
+            b.textContent = 'Log: ' + (logOn ? 'ON' : 'off');
+            b.classList.toggle('danger', logOn);
+            const st = document.getElementById('logState');
+            if (st) {
+                st.textContent = !s.sd ? 'no SD card'
+                    : s.logfile ? ('file: ' + String(s.logfile).split('/').pop())
+                    : (s.ntp ? 'idle' : 'waiting for NTP date');
+            }
+        }
+        function toggleFiles() {
+            const p = document.getElementById('filesPanel');
+            const show = p.style.display === 'none';
+            p.style.display = show ? 'block' : 'none';
+            if (show) refreshLogs();
+        }
+        function refreshLogs() {
+            fetch('/api/logs').then(r => r.json()).then(list => {
+                const t = document.getElementById('filesTable');
+                if (!list.length) { t.innerHTML = '<tr><td style="color:#666;">(no log files yet)</td></tr>'; return; }
+                t.innerHTML = list.map(f =>
+                    `<tr style="border-bottom:1px solid #0f3460;">
+                       <td style="padding:4px 0;">${f.name}${f.active ? ' <span style="color:#4ade80;">(active)</span>' : ''}</td>
+                       <td style="text-align:right; color:#aaa;">${formatBytes(f.size)}</td>
+                       <td style="text-align:right; padding-left:12px;"><a href="/api/logfile?name=${encodeURIComponent(f.name)}" style="color:#60a5fa;">download</a></td>
+                       <td style="text-align:right; padding-left:12px;">${f.active ? '' : `<a href="#" onclick="deleteLog('${f.name}');return false;" style="color:#e94560;">delete</a>`}</td>
+                     </tr>`).join('');
+            }).catch(() => {
+                document.getElementById('filesTable').innerHTML = '<tr><td style="color:#e94560;">(failed -- SD only on T3-S3 build)</td></tr>';
+            });
+        }
+        function deleteLog(name) {
+            if (!confirm('Delete ' + name + '?')) return;
+            fetch('/api/logdelete?name=' + encodeURIComponent(name)).then(() => refreshLogs());
+        }
+        
         // Initial connection
         term.writeln('\x1b[1;36m╔═══════════════════════════════════════╗\x1b[0m');
         term.writeln('\x1b[1;36m║     ESP32 Debug Dongle Terminal       ║\x1b[0m');

platformio.ini

@@ -14,29 +14,92 @@
 platform = espressif32
 board = esp32dev
 framework = arduino
-
-; Serial monitor settings
 monitor_speed = 115200
 monitor_filters = esp32_exception_decoder
 
-; Build flags
+board_build.filesystem = littlefs
+
+; Use a larger app partition (pick ONE):
+board_build.partitions = huge_app.csv      ; 3MB app, 1MB FS, no OTA
+; board_build.partitions = no_ota.csv      ; 2MB app, 2MB FS, no OTA
+; board_build.partitions = min_spiffs.csv  ; 1.9MB app + OTA, 190KB FS
+
 build_flags =
     -DCORE_DEBUG_LEVEL=3
     -DCONFIG_BT_ENABLED=1
     -DCONFIG_BLUEDROID_ENABLED=1
-
+    -DHAS_BT_CLASSIC=1                 ; classic SPP exists on the original ESP32
-; Partition scheme with space for LittleFS
+    -DSTA_SSID="${sysenv.STA_SSID}"
-board_build.partitions = default.csv
+    -DSTA_PASSWORD="${sysenv.STA_PASSWORD}"
-board_build.filesystem = littlefs
 
 ; Libraries
 lib_deps =
-    ; PsychicHttp - robust HTTP server with WebSocket support
+    ; Async Web Server and dependencies
-    hoeken/PsychicHttp @ ^2.1.0
+    https://github.com/ESP32Async/ESPAsyncWebServer
+    https://github.com/ESP32Async/AsyncTCP
 
     ; ArduinoJson for configuration/commands
-    ArduinoJson @ ^7.0.0
+    ArduinoJson
 
 ; Upload settings (adjust port as needed)
 ; upload_port = /dev/ttyUSB0
 ; upload_speed = 921600
+
+; Extra scripts for LittleFS
+extra_scripts =
+    pre:scripts/download_xterm.py
+
+; ============================================================================
+; LilyGo T3-S3 -- ESP32-S3 + SX127x LoRa + SSD1306 128x64 OLED + microSD.
+; The remote debug bridge: UART <-> telnet(:23)/WebSocket, GPIO reset/wake,
+; SD logging (NTP-dated), OLED status. NOTE: ESP32-S3 has NO Bluetooth Classic,
+; so HAS_BT_CLASSIC is NOT set here (telnet + WebSocket replace SerialBT).
+; Pins marked CONFIRM must be checked against your actual board wiring.
+; ============================================================================
+[env:t3s3]
+platform = espressif32
+board = esp32-s3-devkitc-1
+framework = arduino
+monitor_speed = 115200
+monitor_filters = esp32_exception_decoder
+board_build.mcu = esp32s3
+board_build.flash_size = 4MB
+board_upload.flash_size = 4MB
+board_build.filesystem = littlefs
+board_build.partitions = huge_app.csv
+build_flags =
+    -DCORE_DEBUG_LEVEL=3
+    -DARDUINO_USB_CDC_ON_BOOT=1        ; console on USB CDC -> frees UART0 (43/44)
+    ;-DSTA_SSID="${sysenv.STA_SSID}"
+    ;-DSTA_PASSWORD="${sysenv.STA_PASSWORD}"
+    -DSTA_SSID="MeridenRainbow5G"
+    -DSTA_PASSWORD="4z8bcw5vfrs3n7dm"
+    -DBOARD_T3S3=1
+    ; --- OLED (SSD1306 128x64) ---
+    -DT3S3_OLED_SDA=18
+    -DT3S3_OLED_SCL=17
+    -DT3S3_OLED_RST=21
+    -DT3S3_OLED_ADDR=0x3C
+    ; --- target UART bridge (wire to the sensor's debug UART) ---
+    -DTARGET_RX_PIN=44                 ; CONFIRM: dongle RX <- sensor TX
+    -DTARGET_TX_PIN=43                 ; CONFIRM: dongle TX -> sensor RX
+    ; --- GPIO control lines to the target (reset / wake) ---
+    -DGPIO_RESET_PIN=2                 ; CONFIRM: -> sensor RST
+    -DGPIO_WAKE_PIN=1                  ; CONFIRM: -> sensor control/wake pin
+    -DGPIO_CTRL_ACTIVE_LOW=1
+    ; --- microSD on FSPI/SPI2 (separate bus from LoRa, which uses HSPI/SPI3) ---
+    -DT3S3_SD_SCK=14
+    -DT3S3_SD_MISO=2
+    -DT3S3_SD_MOSI=11
+    -DT3S3_SD_CS=13
+    -DT3S3_SD_FREQ_HZ=20000000UL
+    ; --- timezone for NTP-dated logs (Australia/Victoria) ---
+    -DNTP_TZ='"AEST-10AEDT,M10.1.0,M4.1.0/3"'
+lib_deps =
+    https://github.com/ESP32Async/ESPAsyncWebServer
+    https://github.com/ESP32Async/AsyncTCP
+    ArduinoJson
+    adafruit/Adafruit SSD1306
+    adafruit/Adafruit GFX Library
+extra_scripts =
+    pre:scripts/download_xterm.py

src/main.cpp

@@ -1,94 +1,149 @@
 /**
  * ESP32 Debug Dongle
  *
- * Web-based and Bluetooth serial terminal with multi-port support.
+ * Remote serial debug bridge for the trough/solartrack sensors (and anything
+ * with a UART). Bridges a target device's UART to:
+ *   - Telnet (port 23)  -- primary remote path; nc/minicom or an agent
+ *   - Web terminal       -- xterm.js over WebSocket
+ *   - Bluetooth SPP      -- original ESP32 only (no Classic BT on ESP32-S3)
+ * Plus: GPIO control to reset/wake the target, NTP-dated SD logging, and an
+ * OLED status page (LilyGo T3-S3).
  *
- * Features:
+ * Telnet protocol: a line is forwarded verbatim to the target UART UNLESS it
- * - Web terminal using xterm.js over WebSocket
+ * starts with '~', in which case it's a dongle command:
- * - Bluetooth Classic SPP serial bridge
+ *   ~help ~status ~reset [ms] ~wake [ms] ~baud <n> ~port <int|usb|ext>
- * - Switch between internal (virtual), Serial, and Serial1
+ *   ~log on|off  ~gpio <pin> <0|1>
- * - Configurable baud rates
+ * REST mirrors these: /api/status /api/reset /api/wake /api/baud?baud=
+ *   /api/port?port= /api/log?on= /api/gpio?pin=&val= /api/send?data=
  *
- * Hardware connections for Serial1 (external device):
+ * Boards (platformio.ini): [env:esp32dev] generic ESP32 (+ BT); [env:t3s3]
- *   GPIO16 = RX1 (connect to external TX)
+ * LilyGo T3-S3 (OLED + SD + LoRa). Pins are build flags -- see platformio.ini.
- *   GPIO17 = TX1 (connect to external RX)
- *   GND    = Common ground
  */
 
 #include <Arduino.h>
 #include <WiFi.h>
-#include <PsychicHttp.h>
+#include <ESPAsyncWebServer.h>
+#include <AsyncTCP.h>
 #include <LittleFS.h>
 #include <ArduinoJson.h>
-#include "BluetoothSerial.h"
 #include "LoopbackStream.h"
 
+#if HAS_BT_CLASSIC
+#include "BluetoothSerial.h"
+#endif
+
+#if BOARD_T3S3
+#include <time.h>
+#include <Wire.h>
+#include <SPI.h>
+#include <SD.h>
+#include <Adafruit_GFX.h>
+#include <Adafruit_SSD1306.h>
+#endif
+
 // ============================================================================
 // Configuration
 // ============================================================================
 
-// WiFi Mode: Set to true to connect to existing network, false for AP mode
 #define WIFI_STATION_MODE true
+#define ST(A) #A
+#define STR(A) ST(A)
 
-// WiFi Station mode settings (connect to existing network)
+#ifndef STA_SSID
-const char* STA_SSID = "YourNetworkSSID";      // Your WiFi network name
+#define STA_SSID "ExampleSSID"
-const char* STA_PASSWORD = "YourPassword";     // Your WiFi password
+#endif
+#ifndef STA_PASSWORD
+#define STA_PASSWORD "ThePassword"
+#endif
 
-// WiFi Access Point fallback settings (if station fails or AP mode selected)
 const char* AP_SSID = "ESP32-DebugDongle";
-const char* AP_PASSWORD = "debug1234";  // Min 8 characters
+const char* AP_PASSWORD = "debug1234";
-
-// Station mode connection timeout (milliseconds)
 #define WIFI_CONNECT_TIMEOUT 15000
 
-// Bluetooth device name
 const char* BT_NAME = "ESP32-Debug";
 
-// Serial1 pins (external device connection)
+// Target UART pins (override per board in platformio.ini).
-#define SERIAL1_RX_PIN 16
+#ifndef TARGET_RX_PIN
-#define SERIAL1_TX_PIN 17
+#define TARGET_RX_PIN 16
+#endif
+#ifndef TARGET_TX_PIN
+#define TARGET_TX_PIN 17
+#endif
+
+// GPIO control lines to the target. -1 disables. Active-low by default on T3-S3.
+#ifndef GPIO_RESET_PIN
+#define GPIO_RESET_PIN -1
+#endif
+#ifndef GPIO_WAKE_PIN
+#define GPIO_WAKE_PIN -1
+#endif
+#ifndef GPIO_CTRL_ACTIVE_LOW
+#define GPIO_CTRL_ACTIVE_LOW 0
+#endif
 
-// Default baud rates
 #define DEFAULT_BAUD_SERIAL  115200
 #define DEFAULT_BAUD_SERIAL1 115200
-
-// Internal serial buffer size
 #define INTERNAL_BUFFER_SIZE 2048
 
+#define TELNET_PORT     23
+#define MAX_TELNET      4
+#define TELNET_LINE_MAX 256
+#define CTRL_PREFIX     '~'
+
+#if BOARD_T3S3
+#ifndef NTP_TZ
+#define NTP_TZ "UTC0"
+#endif
+#endif
+
 // ============================================================================
 // Global Objects
 // ============================================================================
 
-// PsychicHttp server on port 80
+AsyncWebServer server(80);
-PsychicHttpServer server;
+AsyncWebSocket ws("/ws");
 
-// WebSocket handler
+#if HAS_BT_CLASSIC
-PsychicWebSocketHandler websocketHandler;
-
-// Bluetooth Serial
 BluetoothSerial SerialBT;
+#endif
 
-// Hardware serial for external device
-// HardwareSerial Serial1(1);
-
-// Virtual/loopback serial for internal debug output
 LoopbackStream internalSerial(INTERNAL_BUFFER_SIZE);
-
-// Active serial port pointer
 Stream* activePort = &internalSerial;
 
-// Port identifiers
+enum SerialPortId { PORT_INTERNAL = 0, PORT_USB = 1, PORT_EXTERNAL = 2 };
-enum SerialPortId {
+SerialPortId currentPort = PORT_EXTERNAL;   // default: watch the wired target
-    PORT_INTERNAL = 0,  // Virtual loopback (ESP32 debug output)
-    PORT_USB = 1,       // Serial (USB) - shares with programming
-    PORT_EXTERNAL = 2   // Serial1 (GPIO pins) - external device
-};
-
-SerialPortId currentPort = PORT_INTERNAL;
-
-// Baud rates (can be changed at runtime)
 uint32_t baudSerial1 = DEFAULT_BAUD_SERIAL1;
 
+// Telnet
+WiFiServer telnetServer(TELNET_PORT);
+WiFiClient telnetClients[MAX_TELNET];
+char       telnetLine[MAX_TELNET][TELNET_LINE_MAX];
+size_t     telnetLineLen[MAX_TELNET] = {0};
+
+// Counters
+volatile uint32_t rxBytes = 0;   // from target
+volatile uint32_t txBytes = 0;   // to target
+
+// SD logging (T3-S3)
+bool sdAvailable = false;
+bool logEnabled  = true;          // ON by default once we have a date
+bool ntpSynced   = false;
+#if BOARD_T3S3
+SPIClass sdSPI(FSPI);
+File logFile;
+bool   logAtLineStart = true;
+char   logPath[40] = {0};
+Adafruit_SSD1306 oled(128, 64, &Wire, T3S3_OLED_RST);
+bool oledOk = false;
+#endif
+
+// ============================================================================
+// Forward decls
+// ============================================================================
+void broadcastFromTarget(const uint8_t* data, size_t len);
+void forwardToTarget(const uint8_t* data, size_t len);
+void handleCommand(const char* line, Stream* reply);
+
 // ============================================================================
 // Serial Port Management
 // ============================================================================
@@ -96,27 +151,216 @@ uint32_t baudSerial1 = DEFAULT_BAUD_SERIAL1;
 void setActivePort(SerialPortId port) {
     currentPort = port;
     switch (port) {
-        case PORT_INTERNAL:
+        case PORT_INTERNAL: activePort = &internalSerial; break;
-            activePort = &internalSerial;
+        case PORT_USB:      activePort = &Serial; break;
-            Serial.println("[System] Switched to Internal serial");
+        case PORT_EXTERNAL: activePort = &Serial1; break;
-            break;
-        case PORT_USB:
-            activePort = &Serial;
-            Serial.println("[System] Switched to USB serial");
-            break;
-        case PORT_EXTERNAL:
-            activePort = &Serial1;
-            Serial.println("[System] Switched to External serial (Serial1)");
-            break;
     }
 }
 
-void setBaudRate(SerialPortId port, uint32_t baud) {
+void setBaudRate(uint32_t baud) {
-    if (port == PORT_EXTERNAL) {
     baudSerial1 = baud;
     Serial1.end();
-        Serial1.begin(baud, SERIAL_8N1, SERIAL1_RX_PIN, SERIAL1_TX_PIN);
+    Serial1.begin(baud, SERIAL_8N1, TARGET_RX_PIN, TARGET_TX_PIN);
-        Serial.printf("[System] Serial1 baud rate set to %lu\n", baud);
+}
+
+// ============================================================================
+// GPIO control (reset / wake)
+// ============================================================================
+
+static void gpioInit(int pin) {
+    if (pin < 0) return;
+    // Idle = inactive level.
+    pinMode(pin, OUTPUT);
+    digitalWrite(pin, GPIO_CTRL_ACTIVE_LOW ? HIGH : LOW);
+}
+
+static void gpioPulse(int pin, uint32_t ms, Stream* reply, const char* name) {
+    if (pin < 0) { if (reply) reply->printf("[ctrl] %s pin not configured\r\n", name); return; }
+    if (ms == 0) ms = 200;
+    int active   = GPIO_CTRL_ACTIVE_LOW ? LOW : HIGH;
+    int inactive = GPIO_CTRL_ACTIVE_LOW ? HIGH : LOW;
+    pinMode(pin, OUTPUT);
+    digitalWrite(pin, active);
+    delay(ms);
+    digitalWrite(pin, inactive);
+    if (reply) reply->printf("[ctrl] %s pulsed pin %d for %lu ms\r\n", name, pin, (unsigned long)ms);
+}
+
+// ============================================================================
+// SD logging (T3-S3)
+// ============================================================================
+
+#if BOARD_T3S3
+static void openLogIfReady() {
+    if (!sdAvailable || logFile) return;
+    time_t now = time(nullptr);
+    if (now < 1700000000) return;            // wait for NTP (well past 2023)
+    struct tm tmv; localtime_r(&now, &tmv);
+    SD.mkdir("/logs");
+    strftime(logPath, sizeof(logPath), "/logs/%Y%m%d-%H%M%S.log", &tmv);
+    logFile = SD.open(logPath, FILE_WRITE);
+    if (logFile) {
+        logFile.printf("# debug-dongle log opened %s\n", logPath);
+        logFile.flush();
+        logAtLineStart = true;
+    }
+}
+
+static void logBytes(const uint8_t* data, size_t len) {
+    if (!logEnabled || !logFile) return;
+    for (size_t i = 0; i < len; i++) {
+        if (logAtLineStart) {
+            time_t now = time(nullptr);
+            struct tm tmv; localtime_r(&now, &tmv);
+            char ts[16];
+            strftime(ts, sizeof(ts), "[%H:%M:%S] ", &tmv);
+            logFile.print(ts);
+            logAtLineStart = false;
+        }
+        logFile.write(data[i]);
+        if (data[i] == '\n') logAtLineStart = true;
+    }
+    logFile.flush();                          // power-cut safe (it's a debug log)
+}
+#else
+static void openLogIfReady() {}
+static void logBytes(const uint8_t*, size_t) {}
+#endif
+
+// ============================================================================
+// Fan-out
+// ============================================================================
+
+// Target UART -> every sink (web, telnet, BT, SD).
+void broadcastFromTarget(const uint8_t* data, size_t len) {
+    rxBytes += len;
+    ws.binaryAll((uint8_t*)data, len);
+    for (int i = 0; i < MAX_TELNET; i++)
+        if (telnetClients[i] && telnetClients[i].connected())
+            telnetClients[i].write(data, len);
+#if HAS_BT_CLASSIC
+    if (SerialBT.connected()) SerialBT.write(data, len);
+#endif
+    logBytes(data, len);
+}
+
+// Anything (web/telnet/BT) -> target UART.
+void forwardToTarget(const uint8_t* data, size_t len) {
+    txBytes += len;
+    activePort->write(data, len);
+}
+
+// ============================================================================
+// Command handling (telnet ~cmds and REST share this)
+// ============================================================================
+
+static const char* portName(SerialPortId p) {
+    return p == PORT_INTERNAL ? "internal" : p == PORT_USB ? "usb" : "external";
+}
+
+void printStatus(Stream* o) {
+    o->printf("[status] port=%s baud=%lu rx=%lu tx=%lu telnet=%d log=%s ntp=%s heap=%u\r\n",
+              portName(currentPort), (unsigned long)baudSerial1,
+              (unsigned long)rxBytes, (unsigned long)txBytes,
+              []{ int n=0; for (int i=0;i<MAX_TELNET;i++) if (telnetClients[i]&&telnetClients[i].connected()) n++; return n; }(),
+              logEnabled ? "on" : "off", ntpSynced ? "yes" : "no",
+              (unsigned)ESP.getFreeHeap());
+}
+
+// `line` is the text AFTER the CTRL_PREFIX.
+void handleCommand(const char* line, Stream* reply) {
+    char verb[16] = {0};
+    int n = 0;
+    while (line[n] && line[n] != ' ' && n < 15) { verb[n] = line[n]; n++; }
+    verb[n] = '\0';
+    const char* args = line[n] ? line + n + 1 : line + n;
+
+    if (!strcmp(verb, "help")) {
+        reply->print("[help] ~status ~reset [ms] ~wake [ms] ~baud <n> "
+                     "~port <int|usb|ext> ~log on|off ~gpio <pin> <0|1>\r\n"
+                     "       (any non-~ line is sent to the target UART)\r\n");
+    } else if (!strcmp(verb, "status")) {
+        printStatus(reply);
+    } else if (!strcmp(verb, "reset")) {
+        gpioPulse(GPIO_RESET_PIN, (uint32_t)strtoul(args, nullptr, 10), reply, "reset");
+    } else if (!strcmp(verb, "wake")) {
+        gpioPulse(GPIO_WAKE_PIN, (uint32_t)strtoul(args, nullptr, 10), reply, "wake");
+    } else if (!strcmp(verb, "baud")) {
+        uint32_t b = strtoul(args, nullptr, 10);
+        if (b) { setBaudRate(b); reply->printf("[ctrl] baud=%lu\r\n", (unsigned long)b); }
+        else reply->print("[ctrl] usage: ~baud <n>\r\n");
+    } else if (!strcmp(verb, "port")) {
+        if (!strncmp(args, "int", 3)) setActivePort(PORT_INTERNAL);
+        else if (!strncmp(args, "usb", 3)) setActivePort(PORT_USB);
+        else if (!strncmp(args, "ext", 3)) setActivePort(PORT_EXTERNAL);
+        reply->printf("[ctrl] port=%s\r\n", portName(currentPort));
+    } else if (!strcmp(verb, "log")) {
+#if BOARD_T3S3
+        if (!strncmp(args, "on", 2)) logEnabled = true;
+        else if (!strncmp(args, "off", 3)) logEnabled = false;
+        if (logEnabled) openLogIfReady();
+        reply->printf("[ctrl] log=%s file=%s\r\n", logEnabled ? "on" : "off",
+                      logFile ? logPath : "(none)");
+#else
+        reply->print("[ctrl] no SD on this build\r\n");
+#endif
+    } else if (!strcmp(verb, "gpio")) {
+        int pin = -1, val = 0;
+        if (sscanf(args, "%d %d", &pin, &val) == 2 && pin >= 0) {
+            pinMode(pin, OUTPUT);
+            digitalWrite(pin, val ? HIGH : LOW);
+            reply->printf("[ctrl] gpio %d = %d\r\n", pin, val ? 1 : 0);
+        } else reply->print("[ctrl] usage: ~gpio <pin> <0|1>\r\n");
+    } else {
+        reply->printf("[ctrl] unknown '~%s' (try ~help)\r\n", verb);
+    }
+}
+
+// ============================================================================
+// Telnet
+// ============================================================================
+
+void setupTelnet() { telnetServer.begin(); telnetServer.setNoDelay(true); }
+
+void serviceTelnet() {
+    // Accept new clients into a free slot.
+    if (telnetServer.hasClient()) {
+        int slot = -1;
+        for (int i = 0; i < MAX_TELNET; i++)
+            if (!telnetClients[i] || !telnetClients[i].connected()) { slot = i; break; }
+        WiFiClient c = telnetServer.available();
+        if (slot >= 0) {
+            telnetClients[slot] = c;
+            telnetLineLen[slot] = 0;
+            telnetClients[slot].printf("[dongle] connected -- ~help for commands, "
+                                       "other lines go to the target UART\r\n");
+        } else {
+            c.println("[dongle] too many clients");
+            c.stop();
+        }
+    }
+    // Read each client line-by-line.
+    for (int i = 0; i < MAX_TELNET; i++) {
+        WiFiClient& cl = telnetClients[i];
+        if (!cl || !cl.connected()) continue;
+        while (cl.available()) {
+            char ch = (char)cl.read();
+            if (ch == '\r') continue;
+            if (ch == '\n') {
+                telnetLine[i][telnetLineLen[i]] = '\0';
+                if (telnetLineLen[i] > 0 && telnetLine[i][0] == CTRL_PREFIX) {
+                    handleCommand(telnetLine[i] + 1, &cl);
+                } else {
+                    // Forward the line (with newline) to the target.
+                    forwardToTarget((const uint8_t*)telnetLine[i], telnetLineLen[i]);
+                    const uint8_t nl = '\n';
+                    forwardToTarget(&nl, 1);
+                }
+                telnetLineLen[i] = 0;
+            } else if (telnetLineLen[i] < TELNET_LINE_MAX - 1) {
+                telnetLine[i][telnetLineLen[i]++] = ch;
+            }
+        }
     }
 }
 
@@ -124,299 +368,300 @@ void setBaudRate(SerialPortId port, uint32_t baud) {
 // WebSocket Handlers
 // ============================================================================
 
-void handleWebSocketMessage(PsychicWebSocketClient* client, uint8_t* data, size_t len) {
+void handleWebSocketMessage(AsyncWebSocketClient* client, uint8_t* data, size_t len) {
-    // Check for command prefix (starts with 0x00)
     if (len > 0 && data[0] == 0x00) {
-        // Command message - parse JSON
         String cmdStr = String((char*)(data + 1)).substring(0, len - 1);
         JsonDocument doc;
-        DeserializationError err = deserializeJson(doc, cmdStr);
+        if (deserializeJson(doc, cmdStr)) return;
-
-        if (!err) {
         const char* cmd = doc["cmd"];
-
+        if (!cmd) return;
-            if (strcmp(cmd, "setPort") == 0) {
+        if (!strcmp(cmd, "setPort")) {
-                int port = doc["port"];
+            setActivePort((SerialPortId)(int)doc["port"]);
-                setActivePort((SerialPortId)port);
+        } else if (!strcmp(cmd, "setBaud")) {
-
+            setBaudRate((uint32_t)doc["baud"]);
-                // Send confirmation
+        } else if (!strcmp(cmd, "getStatus")) {
-                String response;
+            String response; JsonDocument r;
-                JsonDocument respDoc;
+            r["type"] = "status";
-                respDoc["type"] = "portChanged";
+            r["currentPort"] = currentPort;
-                respDoc["port"] = port;
+            r["baudSerial1"] = baudSerial1;
-                serializeJson(respDoc, response);
+            r["rx"] = rxBytes; r["tx"] = txBytes;
-
+            r["log"] = logEnabled; r["ntp"] = ntpSynced; r["sd"] = sdAvailable;
-                String msg = String((char)0x00) + response;
+#if BOARD_T3S3
-                client->sendMessage(msg.c_str());
+            r["logfile"] = logFile ? logPath : "";
-            }
+#endif
-            else if (strcmp(cmd, "setBaud") == 0) {
+            r["freeHeap"] = ESP.getFreeHeap();
-                int port = doc["port"];
+            r["wifiMode"] = (WiFi.getMode() == WIFI_STA) ? "station" : "ap";
-                uint32_t baud = doc["baud"];
+            r["ip"] = (WiFi.getMode() == WIFI_STA) ? WiFi.localIP().toString() : WiFi.softAPIP().toString();
-                setBaudRate((SerialPortId)port, baud);
+            serializeJson(r, response);
-            }
+            client->text(String((char)0x00) + response);
-            else if (strcmp(cmd, "getStatus") == 0) {
-                String response;
-                JsonDocument respDoc;
-                respDoc["type"] = "status";
-                respDoc["currentPort"] = currentPort;
-                respDoc["baudSerial1"] = baudSerial1;
-                respDoc["btConnected"] = SerialBT.connected();
-                respDoc["freeHeap"] = ESP.getFreeHeap();
-                respDoc["wifiMode"] = (WiFi.getMode() == WIFI_STA) ? "station" : "ap";
-                respDoc["ip"] = (WiFi.getMode() == WIFI_STA) ? WiFi.localIP().toString() : WiFi.softAPIP().toString();
-                if (WiFi.getMode() == WIFI_STA) {
-                    respDoc["rssi"] = WiFi.RSSI();
-                }
-                serializeJson(respDoc, response);
-
-                String msg = String((char)0x00) + response;
-                client->sendMessage(msg.c_str());
-            }
         }
     } else {
-        // Regular serial data - send to active port
+        forwardToTarget(data, len);
-        activePort->write(data, len);
+    }
+}
+
+void onWsEvent(AsyncWebSocket*, AsyncWebSocketClient* client,
+               AwsEventType type, void* arg, uint8_t* data, size_t len) {
+    if (type == WS_EVT_DATA) {
+        AwsFrameInfo* info = (AwsFrameInfo*)arg;
+        if (info->final && info->index == 0 && info->len == len)
+            handleWebSocketMessage(client, data, len);
     }
 }
 
 // ============================================================================
-// Web Server Setup
+// REST API
 // ============================================================================
 
-void setupWebServer() {
+static String statusJson() {
-    // Increase URI handler limit if needed
-    server.config.max_uri_handlers = 10;
-
-    // Serve static files from LittleFS
-    server.serveStatic("/", LittleFS, "/"); // XXX .setDefaultFile("index.html");
-
-    // API endpoint for status (can be used without WebSocket)
-    server.on("/api/status", HTTP_GET, [](PsychicRequest* request, PsychicResponse* response) {
-        String out;
     JsonDocument doc;
     doc["currentPort"] = currentPort;
     doc["baudSerial1"] = baudSerial1;
-        doc["btConnected"] = SerialBT.connected();
+    doc["rx"] = rxBytes; doc["tx"] = txBytes;
+    doc["log"] = logEnabled; doc["ntp"] = ntpSynced; doc["sd"] = sdAvailable;
+#if BOARD_T3S3
+    doc["logfile"] = logFile ? logPath : "";
+#endif
     doc["freeHeap"] = ESP.getFreeHeap();
     doc["wifiMode"] = (WiFi.getMode() == WIFI_STA) ? "station" : "ap";
     doc["ip"] = (WiFi.getMode() == WIFI_STA) ? WiFi.localIP().toString() : WiFi.softAPIP().toString();
-        doc["ssid"] = (WiFi.getMode() == WIFI_STA) ? WiFi.SSID() : AP_SSID;
+    doc["ssid"] = (WiFi.getMode() == WIFI_STA) ? WiFi.SSID() : String(AP_SSID);
-        if (WiFi.getMode() == WIFI_STA) {
+    if (WiFi.getMode() == WIFI_STA) doc["rssi"] = WiFi.RSSI();
-            doc["rssi"] = WiFi.RSSI();
+    String s; serializeJson(doc, s); return s;
+}
+
+void setupWebServer() {
+    server.serveStatic("/", LittleFS, "/").setDefaultFile("index.html");
+    ws.onEvent(onWsEvent);
+    server.addHandler(&ws);
+
+    server.on("/api/status", HTTP_GET, [](AsyncWebServerRequest* req) {
+        req->send(200, "application/json", statusJson());
+    });
+    server.on("/api/reset", HTTP_GET, [](AsyncWebServerRequest* req) {
+        uint32_t ms = req->hasParam("ms") ? req->getParam("ms")->value().toInt() : 0;
+        gpioPulse(GPIO_RESET_PIN, ms, nullptr, "reset");
+        req->send(200, "text/plain", "reset pulsed\n");
+    });
+    server.on("/api/wake", HTTP_GET, [](AsyncWebServerRequest* req) {
+        uint32_t ms = req->hasParam("ms") ? req->getParam("ms")->value().toInt() : 0;
+        gpioPulse(GPIO_WAKE_PIN, ms, nullptr, "wake");
+        req->send(200, "text/plain", "wake pulsed\n");
+    });
+    server.on("/api/baud", HTTP_GET, [](AsyncWebServerRequest* req) {
+        if (req->hasParam("baud")) setBaudRate(req->getParam("baud")->value().toInt());
+        req->send(200, "application/json", statusJson());
+    });
+    server.on("/api/port", HTTP_GET, [](AsyncWebServerRequest* req) {
+        if (req->hasParam("port")) {
+            String p = req->getParam("port")->value();
+            if (p.startsWith("int")) setActivePort(PORT_INTERNAL);
+            else if (p.startsWith("usb")) setActivePort(PORT_USB);
+            else if (p.startsWith("ext")) setActivePort(PORT_EXTERNAL);
         }
-        serializeJson(doc, out);
+        req->send(200, "application/json", statusJson());
-        return response->send(200, "application/json", out.c_str());
+    });
+    server.on("/api/log", HTTP_GET, [](AsyncWebServerRequest* req) {
+        if (req->hasParam("on")) {
+            logEnabled = req->getParam("on")->value().toInt() != 0;
+            if (logEnabled) openLogIfReady();
+        }
+        req->send(200, "application/json", statusJson());
+    });
+    server.on("/api/gpio", HTTP_GET, [](AsyncWebServerRequest* req) {
+        if (req->hasParam("pin") && req->hasParam("val")) {
+            int pin = req->getParam("pin")->value().toInt();
+            int val = req->getParam("val")->value().toInt();
+            if (pin >= 0) { pinMode(pin, OUTPUT); digitalWrite(pin, val ? HIGH : LOW); }
+        }
+        req->send(200, "text/plain", "ok\n");
+    });
+    server.on("/api/send", HTTP_GET, [](AsyncWebServerRequest* req) {
+        if (req->hasParam("data")) {
+            String d = req->getParam("data")->value();
+            forwardToTarget((const uint8_t*)d.c_str(), d.length());
+            const uint8_t nl = '\n'; forwardToTarget(&nl, 1);
+        }
+        req->send(200, "text/plain", "sent\n");
     });
 
-    // WebSocket handler callbacks
+#if BOARD_T3S3
-    websocketHandler.onOpen([](PsychicWebSocketClient* client) {
+    // List SD log files: JSON [{name,size,active}].
-        Serial.printf("[WS] Client #%u connected from %s\n",
+    server.on("/api/logs", HTTP_GET, [](AsyncWebServerRequest* req) {
-                     client->socket(), client->remoteIP().toString().c_str());
+        JsonDocument doc; JsonArray arr = doc.to<JsonArray>();
+        File dir = SD.open("/logs");
+        if (dir && dir.isDirectory()) {
+            for (File f = dir.openNextFile(); f; f = dir.openNextFile()) {
+                if (f.isDirectory()) continue;
+                const char* n = f.name();
+                const char* base = strrchr(n, '/'); base = base ? base + 1 : n;
+                JsonObject o = arr.add<JsonObject>();
+                o["name"] = base;
+                o["size"] = (uint32_t)f.size();
+                o["active"] = (logFile && strcmp(logPath, n) == 0);
+            }
+        }
+        String s; serializeJson(doc, s);
+        req->send(200, "application/json", s);
     });
-
+    // Download a log file. ?name=<basename> (no slashes).
-    websocketHandler.onFrame([](PsychicWebSocketRequest* request, httpd_ws_frame* frame) {
+    server.on("/api/logfile", HTTP_GET, [](AsyncWebServerRequest* req) {
-        handleWebSocketMessage(request->client(), frame->payload, frame->len);
+        if (!req->hasParam("name")) { req->send(400, "text/plain", "name?\n"); return; }
-        return ESP_OK;
+        String name = req->getParam("name")->value();
+        if (name.indexOf('/') >= 0 || name.indexOf("..") >= 0) { req->send(400, "text/plain", "bad name\n"); return; }
+        String p = "/logs/" + name;
+        if (!SD.exists(p)) { req->send(404, "text/plain", "not found\n"); return; }
+        if (logFile) logFile.flush();             // flush in-flight bytes first
+        req->send(SD, p, "text/plain", true);     // true => download
     });
-
+    // Delete a log file (refuses the currently-open one).
-    websocketHandler.onClose([](PsychicWebSocketClient* client) {
+    server.on("/api/logdelete", HTTP_GET, [](AsyncWebServerRequest* req) {
-        Serial.printf("[WS] Client #%u disconnected\n", client->socket());
+        if (!req->hasParam("name")) { req->send(400, "text/plain", "name?\n"); return; }
+        String name = req->getParam("name")->value();
+        if (name.indexOf('/') >= 0 || name.indexOf("..") >= 0) { req->send(400, "text/plain", "bad name\n"); return; }
+        String p = "/logs/" + name;
+        if (logFile && strcmp(logPath, p.c_str()) == 0) { req->send(409, "text/plain", "active log -- ~log off first\n"); return; }
+        bool ok = SD.remove(p);
+        req->send(ok ? 200 : 404, "text/plain", ok ? "deleted\n" : "not found\n");
     });
+#endif
 
-    // Attach WebSocket handler to /ws endpoint
+    server.onNotFound([](AsyncWebServerRequest* req) { req->send(404, "text/plain", "Not found"); });
-    server.on("/ws", &websocketHandler);
-
-    // Start the server
     server.begin();
-    Serial.println("[Web] Server started");
 }
 
 // ============================================================================
-// WiFi Setup
+// WiFi
 // ============================================================================
 
 bool connectToWiFi() {
-    Serial.printf("[WiFi] Connecting to %s", STA_SSID);
-
     WiFi.mode(WIFI_STA);
-    WiFi.begin(STA_SSID, STA_PASSWORD);
+    WiFi.begin(STR(STA_SSID), STR(STA_PASSWORD));
-
+    unsigned long t0 = millis();
-    unsigned long startTime = millis();
     while (WiFi.status() != WL_CONNECTED) {
-        if (millis() - startTime > WIFI_CONNECT_TIMEOUT) {
+        if (millis() - t0 > WIFI_CONNECT_TIMEOUT) return false;
-            Serial.println(" TIMEOUT");
+        delay(500); Serial.print(".");
-            return false;
     }
-        delay(500);
+    Serial.printf("\n[WiFi] %s  IP %s  %d dBm\n", STR(STA_SSID),
-        Serial.print(".");
+                  WiFi.localIP().toString().c_str(), WiFi.RSSI());
-    }
-
-    Serial.println(" OK");
-    Serial.printf("[WiFi] Connected to: %s\n", STA_SSID);
-    Serial.printf("[WiFi] IP Address: %s\n", WiFi.localIP().toString().c_str());
-    Serial.printf("[WiFi] Signal strength: %d dBm\n", WiFi.RSSI());
     return true;
 }
 
 void startAccessPoint() {
     WiFi.mode(WIFI_AP);
     WiFi.softAP(AP_SSID, AP_PASSWORD);
-
+    Serial.printf("[WiFi] AP %s  IP %s\n", AP_SSID, WiFi.softAPIP().toString().c_str());
-    IPAddress ip = WiFi.softAPIP();
-    Serial.println("[WiFi] Access Point started");
-    Serial.printf("[WiFi] SSID: %s\n", AP_SSID);
-    Serial.printf("[WiFi] Password: %s\n", AP_PASSWORD);
-    Serial.printf("[WiFi] IP Address: %s\n", ip.toString().c_str());
 }
 
 void setupWiFi() {
-    WiFi.disconnect(true);  // Clear any previous connection
+    WiFi.disconnect(true); delay(100);
-    delay(100);
+    if (!WIFI_STATION_MODE || !connectToWiFi()) startAccessPoint();
-
-    if (WIFI_STATION_MODE) {
-        // Try to connect to existing network
-        if (!connectToWiFi()) {
-            Serial.println("[WiFi] Station mode failed, falling back to AP mode");
-            startAccessPoint();
-        }
-    } else {
-        // Start as Access Point directly
-        startAccessPoint();
-    }
 }
 
 // ============================================================================
-// Bluetooth Setup
+// T3-S3 peripherals: NTP, SD, OLED
 // ============================================================================
 
-void setupBluetooth() {
+#if BOARD_T3S3
-    if (!SerialBT.begin(BT_NAME)) {
+void setupSD() {
-        Serial.println("[BT] Failed to initialize Bluetooth");
+    sdSPI.begin(T3S3_SD_SCK, T3S3_SD_MISO, T3S3_SD_MOSI, T3S3_SD_CS);
-        return;
+    sdAvailable = SD.begin(T3S3_SD_CS, sdSPI, T3S3_SD_FREQ_HZ);
-    }
+    Serial.printf("[SD] %s (CS=%d)\n", sdAvailable ? "mounted" : "NOT found -- check T3S3_SD_* pins",
-    Serial.printf("[BT] Bluetooth started as '%s'\n", BT_NAME);
+                  T3S3_SD_CS);
-    Serial.println("[BT] Ready for pairing");
 }
 
-// ============================================================================
+void setupNTP() { configTzTime(NTP_TZ, "pool.ntp.org", "time.google.com"); }
-// Debug Output Helper
-// ============================================================================
 
-// Use this function in your code to write to the internal virtual serial
+void setupOLED() {
-// These messages will be visible when PORT_INTERNAL is selected
+    Wire.begin(T3S3_OLED_SDA, T3S3_OLED_SCL);
-void debugPrint(const char* format, ...) {
+    oledOk = oled.begin(SSD1306_SWITCHCAPVCC, T3S3_OLED_ADDR);
-    char buffer[256];
+    if (oledOk) { oled.clearDisplay(); oled.setTextColor(SSD1306_WHITE); oled.setTextSize(1); oled.display(); }
-    va_list args;
+    Serial.printf("[OLED] %s\n", oledOk ? "ok" : "NOT found");
-    va_start(args, format);
-    vsnprintf(buffer, sizeof(buffer), format, args);
-    va_end(args);
-
-    internalSerial.print(buffer);
 }
 
-void debugPrintln(const char* format, ...) {
+void renderOLED() {
-    char buffer[256];
+    if (!oledOk) return;
-    va_list args;
+    int clients = 0;
-    va_start(args, format);
+    for (int i = 0; i < MAX_TELNET; i++) if (telnetClients[i] && telnetClients[i].connected()) clients++;
-    vsnprintf(buffer, sizeof(buffer), format, args);
+    String ip = (WiFi.getMode() == WIFI_STA) ? WiFi.localIP().toString() : WiFi.softAPIP().toString();
-    va_end(args);
+    oled.clearDisplay();
-
+    oled.setCursor(0, 0);  oled.println(ip);
-    internalSerial.println(buffer);
+    oled.setCursor(0, 10); oled.printf("%s %ddBm\n",
+        (WiFi.getMode()==WIFI_STA)?WiFi.SSID().c_str():AP_SSID,
+        (WiFi.getMode()==WIFI_STA)?WiFi.RSSI():0);
+    oled.setCursor(0, 20); oled.printf("uart %d/%d %lu\n", TARGET_RX_PIN, TARGET_TX_PIN, (unsigned long)baudSerial1);
+    oled.setCursor(0, 30); oled.printf("rx %lu tx %lu\n", (unsigned long)rxBytes, (unsigned long)txBytes);
+    oled.setCursor(0, 40); oled.printf("telnet %d  log %s\n", clients, (logEnabled && logFile) ? "ON" : "off");
+    oled.setCursor(0, 50); oled.printf("ntp %s sd %s\n", ntpSynced ? "ok" : "--", sdAvailable ? "ok" : "--");
+    oled.display();
 }
+#endif
 
 // ============================================================================
-// Main Setup
+// Setup / Loop
 // ============================================================================
 
 void setup() {
-    // Initialize USB serial (for local debugging)
     Serial.begin(DEFAULT_BAUD_SERIAL);
-    delay(1000);
+    delay(500);
+    Serial.println("\n=== ESP32 Debug Dongle ===");
 
-    Serial.println("\n\n========================================");
+    Serial1.begin(baudSerial1, SERIAL_8N1, TARGET_RX_PIN, TARGET_TX_PIN);
-    Serial.println("  ESP32 Debug Dongle (PsychicHttp)");
+    Serial.printf("[Serial1] %lu baud RX=%d TX=%d\n", baudSerial1, TARGET_RX_PIN, TARGET_TX_PIN);
-    Serial.println("========================================\n");
 
-    // Initialize Serial1 for external device
+    gpioInit(GPIO_RESET_PIN);
-    Serial1.begin(baudSerial1, SERIAL_8N1, SERIAL1_RX_PIN, SERIAL1_TX_PIN);
+    gpioInit(GPIO_WAKE_PIN);
-    Serial.printf("[Serial1] Initialized at %lu baud (RX=%d, TX=%d)\n",
+    setActivePort(currentPort);
-                  baudSerial1, SERIAL1_RX_PIN, SERIAL1_TX_PIN);
 
-    // Initialize LittleFS
+    if (!LittleFS.begin(true)) Serial.println("[FS] LittleFS mount failed");
-    if (!LittleFS.begin(true)) {
+
-        Serial.println("[FS] LittleFS mount failed!");
+#if BOARD_T3S3
-    } else {
+    setupOLED();
-        Serial.println("[FS] LittleFS mounted");
+    setupSD();
-    }
+#endif
 
-    // Setup WiFi Access Point
     setupWiFi();
 
-    // Setup Bluetooth
+#if BOARD_T3S3
-    setupBluetooth();
+    if (WiFi.getMode() == WIFI_STA) setupNTP();
+#endif
 
-    // Setup Web Server
+#if HAS_BT_CLASSIC
+    if (SerialBT.begin(BT_NAME)) Serial.printf("[BT] '%s' ready\n", BT_NAME);
+#endif
+
+    setupTelnet();
     setupWebServer();
 
-    Serial.println("\n[System] Ready!");
     String ip = (WiFi.getMode() == WIFI_STA) ? WiFi.localIP().toString() : WiFi.softAPIP().toString();
-    Serial.printf("[System] Open http://%s in browser\n", ip.c_str());
+    Serial.printf("[Ready] http://%s   telnet %s 23\n", ip.c_str(), ip.c_str());
-    Serial.println("[System] Or connect via Bluetooth\n");
-
-    // Send initial message to internal serial
-    debugPrintln("ESP32 Debug Dongle initialized");
-    debugPrintln("Free heap: %d bytes", ESP.getFreeHeap());
 }
 
-// ============================================================================
-// Main Loop
-// ============================================================================
-
-// Buffer for efficient serial reading
 static uint8_t serialBuffer[256];
 
 void loop() {
-    // Read from active serial port and send to WebSocket + Bluetooth
+    // Target UART -> sinks
-    size_t available = activePort->available();
+    size_t avail = activePort->available();
-    if (available > 0) {
+    if (avail > 0) {
-        size_t toRead = min(available, sizeof(serialBuffer));
+        size_t toRead = min(avail, sizeof(serialBuffer));
-        size_t bytesRead = 0;
+        size_t got = 0;
-
+        for (size_t i = 0; i < toRead; i++) { int c = activePort->read(); if (c >= 0) serialBuffer[got++] = (uint8_t)c; }
-        // Read bytes into buffer
+        if (got > 0) broadcastFromTarget(serialBuffer, got);
-        for (size_t i = 0; i < toRead; i++) {
-            int c = activePort->read();
-            if (c >= 0) {
-                serialBuffer[bytesRead++] = (uint8_t)c;
-            }
     }
 
-        if (bytesRead > 0) {
+#if HAS_BT_CLASSIC
-            // Send to all WebSocket clients (PsychicHttp uses sendAll)
+    while (SerialBT.available()) { int c = SerialBT.read(); if (c >= 0) { uint8_t b = (uint8_t)c; forwardToTarget(&b, 1); } }
-            websocketHandler.sendAll((char*)serialBuffer, bytesRead);
+#endif
 
-            // Send to Bluetooth if connected
+    serviceTelnet();
-            if (SerialBT.connected()) {
+    ws.cleanupClients();
-                SerialBT.write(serialBuffer, bytesRead);
-            }
-        }
-    }
 
-    // Read from Bluetooth and send to active serial port
+#if BOARD_T3S3
-    while (SerialBT.available()) {
+    // Once NTP lands, mark synced + open today's log.
-        int c = SerialBT.read();
+    if (!ntpSynced && time(nullptr) > 1700000000) { ntpSynced = true; if (logEnabled) openLogIfReady(); }
-        if (c >= 0) {
+    static unsigned long lastOled = 0;
-            activePort->write((uint8_t)c);
+    if (millis() - lastOled > 500) { lastOled = millis(); renderOLED(); }
-        }
+#endif
-    }
 
-    // Periodic internal debug messages (example)
-    static unsigned long lastDebug = 0;
-    if (millis() - lastDebug > 30000) {  // Every 30 seconds
-        lastDebug = millis();
-        debugPrintln("[%lu] Heartbeat - Heap: %d, WS clients: %d",
-                    millis() / 1000, ESP.getFreeHeap(), websocketHandler.count());
-    }
-
-    // Small delay to prevent WDT issues
     delay(1);
 }