diff --git a/pm3py/client.py b/pm3py/client.py
index 6dc3680..8c16bff 100644
--- a/pm3py/client.py
+++ b/pm3py/client.py
@@ -1,5 +1,8 @@
 """Main Proxmark3 client with nested API."""
-from .transport import PM3Transport, PM3Response, ProgressCallback
+import logging
+from dataclasses import dataclass, field
+
+from .transport import PM3Transport, PM3Response, PM3Error, ProgressCallback
 from .hw import HWCommands
 from .lf import LFCommands
 from .hf import HFCommands
@@ -7,12 +10,27 @@ from .hf_14a import HF14ACommands
 from .hf_15 import HF15Commands
 from .hf_mf import HFMFCommands
 
+log = logging.getLogger(__name__)
+
+
+@dataclass
+class FirmwareInfo:
+    """Firmware version and compatibility information populated on connect."""
+    version_string: str = ""
+    chip_id: str = ""
+    section_size: int = 0
+    ng_protocol: bool = False
+    compatible: bool = False
+    warnings: list[str] = field(default_factory=list)
+
 
 class Proxmark3:
     """Proxmark3 device client with structured Python API.
 
     Usage:
         async with Proxmark3("/dev/ttyACM0") as pm3:
+            if not pm3.firmware.compatible:
+                print("Warnings:", pm3.firmware.warnings)
             status = await pm3.hw.version()
             print(status)
 
@@ -28,9 +46,11 @@ class Proxmark3:
         self.hf.a14 = HF14ACommands(self._transport)
         self.hf.iso15 = HF15Commands(self._transport)
         self.hf.mf = HFMFCommands(self._transport)
+        self.firmware = FirmwareInfo()
 
     async def connect(self) -> None:
         await self._transport.connect()
+        await self._probe_firmware()
 
     async def disconnect(self) -> None:
         await self._transport.disconnect()
@@ -42,6 +62,36 @@ class Proxmark3:
     async def __aexit__(self, *args) -> None:
         await self.disconnect()
 
+    async def _probe_firmware(self) -> None:
+        """Ping device and fetch firmware version after connecting."""
+        fw = self.firmware
+        fw.warnings = []
+
+        # Step 1: Ping to verify NG protocol support
+        try:
+            ping_result = await self.hw.ping(32)
+            fw.ng_protocol = ping_result.get("success", False)
+            if not fw.ng_protocol:
+                fw.warnings.append("Ping echo mismatch — device may not support NG protocol")
+        except PM3Error:
+            fw.ng_protocol = False
+            fw.warnings.append("Ping failed — device may not support NG protocol or may be in bootloader mode")
+
+        # Step 2: Fetch firmware version
+        try:
+            ver = await self.hw.version()
+            fw.version_string = ver.get("version_string", "")
+            fw.chip_id = ver.get("chip_id", "")
+            fw.section_size = ver.get("section_size", 0)
+        except PM3Error:
+            fw.warnings.append("Could not read firmware version — device may be in bootloader mode")
+
+        # Step 3: Assess compatibility
+        fw.compatible = fw.ng_protocol and len(fw.warnings) == 0
+
+        for w in fw.warnings:
+            log.warning("pm3py: %s", w)
+
     async def send_ng(self, cmd: int, payload: bytes = b"",
                       timeout: float = 2.0) -> PM3Response:
         """Raw NG command -- escape hatch for unwrapped commands."""
diff --git a/tests/test_integration.py b/tests/test_integration.py
index 65d4c1c..9537270 100644
--- a/tests/test_integration.py
+++ b/tests/test_integration.py
@@ -3,6 +3,7 @@ import struct
 import asyncio
 from unittest.mock import AsyncMock, MagicMock
 from pm3py import Proxmark3, Cmd
+from pm3py.client import FirmwareInfo
 
 
 def test_full_api_surface():
@@ -18,6 +19,8 @@ def test_full_api_surface():
     assert hasattr(pm3.hf, "mf")
     assert hasattr(pm3, "send_ng")
     assert hasattr(pm3, "send_mix")
+    assert hasattr(pm3, "firmware")
+    assert isinstance(pm3.firmware, FirmwareInfo)
 
 
 def test_hw_ping_roundtrip():
@@ -47,3 +50,52 @@ def test_mf_rdbl_returns_hex():
         pm3.hf.mf.rdbl(block=4, key="FFFFFFFFFFFF"))
     assert result["data"] == "000102030405060708090a0b0c0d0e0f"
     assert result["raw"] == block
+
+
+def test_firmware_probe_compatible():
+    """Verify firmware probe populates FirmwareInfo on successful connect."""
+    pm3 = Proxmark3("/dev/null")
+    mock_transport = AsyncMock()
+    pm3._transport = mock_transport
+    pm3.hw._t = mock_transport
+
+    from pm3py.transport import PM3Response
+
+    ping_data = bytes(range(32))
+    vstr = b"Proxmark3 RDV4.0 FW v4.18000\x00"
+    version_payload = struct.pack("<III", 0x270B0A40, 512*1024, len(vstr)) + vstr
+
+    # send_ng called twice: once for ping, once for version
+    mock_transport.send_ng.side_effect = [
+        PM3Response(cmd=Cmd.PING, status=0, reason=0, ng=True, data=ping_data),
+        PM3Response(cmd=Cmd.VERSION, status=0, reason=0, ng=True, data=version_payload),
+    ]
+
+    asyncio.get_event_loop().run_until_complete(pm3._probe_firmware())
+    assert pm3.firmware.compatible is True
+    assert pm3.firmware.ng_protocol is True
+    assert "Proxmark3 RDV4.0" in pm3.firmware.version_string
+    assert pm3.firmware.warnings == []
+
+
+def test_firmware_probe_ping_fails():
+    """Verify firmware probe marks incompatible when ping fails."""
+    pm3 = Proxmark3("/dev/null")
+    mock_transport = AsyncMock()
+    pm3._transport = mock_transport
+    pm3.hw._t = mock_transport
+
+    from pm3py.transport import PM3Response, PM3Error
+
+    vstr = b"Proxmark3 OLD\x00"
+    version_payload = struct.pack("<III", 0x270B0A40, 256*1024, len(vstr)) + vstr
+
+    mock_transport.send_ng.side_effect = [
+        PM3Error("Ping failed"),
+        PM3Response(cmd=Cmd.VERSION, status=0, reason=0, ng=True, data=version_payload),
+    ]
+
+    asyncio.get_event_loop().run_until_complete(pm3._probe_firmware())
+    assert pm3.firmware.compatible is False
+    assert pm3.firmware.ng_protocol is False
+    assert len(pm3.firmware.warnings) > 0