StamPLC: boot_option=2 ("only network setup") never connects Wi-Fi because PoEStamPLC() is created unconditionally #116

Environment

• Board: M5Stack StamPLC (K141), no PoE module attached (Wi-Fi only, net_mode = "WIFI")
• Firmware: uiflow-50e4407-esp32s3-8mb-stamplc-v2.5.3-20260911.bin (UIFlow2 v2.5.3, commit 50e4407). The code on master (2026-10-09) is the same.
• uiflow NVS: boot_option = 2, net_mode = "WIFI", ssid0 / pswd0 set (the same credentials connect fine from the startup menu and from user code).

Steps to reproduce

1. Set boot_option to 2 (e.g. esp32.NVS("uiflow").set_u8("boot_option", 2)), reboot.
2. Wait 40 s. network.WLAN(network.STA_IF).isconnected() is still False.
3. Calling the same path from the REPL shows the cause:

>>> import startup
>>> startup.startup(2, 60)
Startup with network type: WIFI
WiFi initialized
hw_spi: SPI bus already initialized
esp_eth_driver_install failed with error code 263
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "startup/__init__.py", line 1, in startup
  File "startup/__init__.py", line 1, in _connect_network_only
  File "stamplc/poe.py", line 43, in __new__
OSError: esp_eth_driver_install failed

Cause

In m5stack/modules/startup/__init__.py, _connect_network_only() instantiates the PoE Ethernet driver for StamPLC regardless of net_mode:

def _connect_network_only(board_id, net_mode, ssid, pswd):
    startup = Startup(network_type=net_mode)
    lan_if = None
    if board_id == M5.BOARD.M5Unit_PoEP4:
        from driver.ip101gri import IP101GRI
        lan_if = IP101GRI(mdc_pin=31, mdio_pin=52, power_pin=51)
    elif board_id == M5.BOARD.M5StamPLC:
        from stamplc import PoEStamPLC
        lan_if = PoEStamPLC()          # raises OSError when the PoE module is absent
    startup.connect_network(ssid, pswd, lan_if)

Without the PoE module, PoEStamPLC() fails with esp_eth_driver_install failed (263 = ESP_ERR_TIMEOUT) and the exception propagates before connect_network() is reached, so Wi-Fi is never started. The startup menu path (boot_option = 1, startup/stamplc/__init__.py) only creates PoEStamPLC() when net_mode == "ETH", so it is not affected.

Expected

With net_mode = "WIFI", boot_option = 2 should start the Wi-Fi connection exactly like the startup menu does, whether or not a PoE module is attached.

Proposed fix

Create the PoE interface only when Ethernet is selected, matching the StamPLC startup menu:

     elif board_id == M5.BOARD.M5StamPLC:
-        from stamplc import PoEStamPLC
-        lan_if = PoEStamPLC()
+        if net_mode == "ETH":
+            from stamplc import PoEStamPLC
+            lan_if = PoEStamPLC()
     startup.connect_network(ssid, pswd, lan_if)

(Alternatively wrap PoEStamPLC() in try/except OSError and fall back to Wi-Fi.)

Workaround used meanwhile

Keep boot_option = 0 and start the connection from user code with the firmware's own class:

from startup import Startup
Startup(network_type="WIFI").connect_network(ssid, pswd)

This connects in about 2 s on the same device.