Accessing the BLE signal strength in the calling program.

[WPS12TA]

Feature Request: Add BLE RSSI (BLE Signal Strength) Access to calling program.

RadiaCode Library - BLE RSSI Patch

Status: TESTED AND WORKING
Date: March 2026
Compatible With: RadiaCode library by Markus Geiger (mkgeiger)

This patch adds RSSI (signal strength) access to the RadiaCode Arduino library.

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What This Patch Does

Adds a getRSSI() method to access BLE signal strength from your RadiaCode device.

Returns:

• -30 to -90 dBm: Connected (typical range)
• -100: Not connected or error

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Installation Instructions

You need to edit 4 files in your RadiaCode library folder:

Location: Documents/Arduino/libraries/RadiaCode/src/

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FILE 1: BluetoothTransport.h

FIND the public section:

public:
    BluetoothTransport(const char* mac);
    virtual ~BluetoothTransport(void);
    virtual BytesBuffer execute(const uint8_t* request, size_t length) override;

ADD this line after the execute() line:

    int getRSSI();  // Get BLE signal strength

Result should look like:

public:
    BluetoothTransport(const char* mac);
    virtual ~BluetoothTransport(void);
    virtual BytesBuffer execute(const uint8_t* request, size_t length) override;
    int getRSSI();  // Get BLE signal strength

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FILE 2: BluetoothTransport.cpp

SCROLL TO THE VERY END of the file (after the last function's closing brace)

ADD this complete function:

int BluetoothTransport::getRSSI() {
#ifdef BT_SUPPORT_ENABLED
    if (_peripheral) {
        BLEClient* pClient = (BLEClient*)_peripheral;
        if (pClient->isConnected()) {
            return pClient->getRssi();
        }
    }
#endif
    return -100;  // Not connected
}

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FILE 3: RadiaCode.h

FIND the public section (around line 90):

    // Direct sensor reading methods
    float getTemperature(void);

ADD this line after getTemperature():

    int getRSSI();  // Get BLE signal strength in dBm

Result should look like:

    // Direct sensor reading methods
    float getTemperature(void);
    int getRSSI();  // Get BLE signal strength in dBm

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FILE 4: RadiaCode.cpp

FIRST - Check the #include section at the top of the file.

MAKE SURE this line exists (add it if missing):

#include "BluetoothTransport.h"

THEN - SCROLL TO THE VERY END of the file (after the last function)

ADD this complete function:

int RadiaCode::getRSSI() {
    if (!_connection) {
        return -100;  // No connection
    }
    // Safe cast on ESP32 - _connection is always BluetoothTransport
    BluetoothTransport* bt = (BluetoothTransport*)_connection;
    return bt->getRSSI();
}

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⚠️ Critical Notes

1. Add Functions at the END of Files

DO NOT add functions INSIDE other functions!

• Always add at the END of .cpp files
• Look for the last closing brace } of existing code
• Add your new function AFTER that

2. Use C-Style Cast (Not dynamic_cast)

Arduino doesn't support RTTI, so use simple casting:

// ✅ CORRECT - C-style cast
BluetoothTransport* bt = (BluetoothTransport*)_connection;

// ❌ WRONG - dynamic_cast not supported
BluetoothTransport* bt = dynamic_cast<BluetoothTransport*>(_connection);

3. Include BluetoothTransport.h

Make sure RadiaCode.cpp includes the header:

#include "BluetoothTransport.h"

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Usage in Your Sketch

After patching, you can use:

RadiaCode* radiacode = new RadiaCode(RADIACODE_MAC);
int blerssi = radiacode->getRSSI();

Serial.printf("BLE Signal: %d dBm\n", blerssi);

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Signal Quality Guide

RSSI (dBm)	Quality	Description
-30 to -50	Excellent	Very close, strong signal
-50 to -60	Good	Normal operating distance
-60 to -70	Fair	Edge of reliable range
-70 to -90	Weak	Connection may be unstable
-90 to -100	Very weak	About to disconnect
-100	Disconnected	No connection

More negative = weaker signal

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Test it:

void loop() {
    int blerssi = radiacode->getRSSI();
    if (blerssi != -100) {
        Serial.printf("BLE RSSI: %d dBm\n", blerssi);
    }
    delay(5000);
}

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Why This Patch is Needed

The RadiaCode library doesn't expose RSSI by default. This patch:

1. Adds getRSSI() to BluetoothTransport (accesses BLE client)
2. Adds getRSSI() to RadiaCode (public API)
3. Uses safe casting to access the underlying BLE client
4. Returns -100 when not connected (safe default)

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Tested With

• Arduino IDE: 1.8.19
• Board: ESP32S3 Dev Module
• RadiaCode Library: Version by Markus Geiger (mkgeiger)
• Device: RadiaCode-110
• Date: March 2026

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Request to the RadiaCode library repository so all users can benefit from RSSI access!

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Version: 1.0 (Final)
Author: Based on RadiaCode ESP32 Monitor project
License: Same as RadiaCode library