Add Arduino Nano 33 BLE Sense board support

[Copilot]

The Arduino Nano 33 BLE Sense (u-blox NINA-B306 / nRF52840) was not supported in n-able-Arduino despite being listed on Arduino's NimBLE library docs page.

Changes

variants/Arduino_Nano33BLE_Sense/variant.h

• Full pin definitions matching the official ArduinoCore-mbed mapping: D0–D13, A0–A7, RGB LEDs, power LED, SPI, I2C (external Wire + internal Wire1 for sensors), UART, PDM mic (MP34DT05), APDS9960 interrupt, and sensor power control pins
• USE_LFXO — NINA-B306 has an onboard 32.768 kHz crystal
• 34 total pins (14 digital, 8 analog, 12 internal)

variants/Arduino_Nano33BLE_Sense/variant.cpp

• g_ADigitalPinMap[] mapping all 34 Arduino indices to nRF52840 GPIO numbers, verified against the ArduinoCore-mbed variant.cpp
• initVariant() enables the power LED and asserts the sensors 3.3V rail and I2C pull-up enable pins — required for onboard sensors (LSM9DS1, HTS221, LPS22HB, APDS9960) to function

boards.txt

• New # Arduino section with nano33blesense entry
• VID 0x2341, PIDs 0x805a / 0x005a / 0x025a / 0x015a
• OpenOCD upload with 1200bps touch reset
• Bootloader menu: Adafruit BLE (s140 v7), Adafruit Serial, No bootloader
• BLE role and debug level menus consistent with other nRF52840 boards

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Where is Arduino Nano 33 BLE Sense support?</issue_title>
<issue_description>According to the Arduino docs website many Arduino boards are supported by arm-able. But there are none listed on the website.

https://docs.arduino.cc/libraries/nimble-arduino/</issue_description>

<agent_instructions>copy the variant files and linker required to support this in the same way the seeed nrf52840 is supported
</agent_instructions>

Comments on the Issue (you are @copilot in this section)

@h2zero It's a work in progress, the goal is to support as many devices as possible but it takes a lot of time to add them. @h2zero Not at this time, if I had the memory map for it I could add it.

• Fixes Where is Arduino Nano 33 BLE Sense support? #70

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