From PINE64
Jump to navigation Jump to search
PineCone BL602 EVB (Evaluation Board)

The PineCone is a BL602 evaluation board, which was developed with the goal to challenge the open source community to achieve blob-free and free and open source WiFi and Bluetooth, see the Nutcracker Challenge.


The goal of the challenge is to achieve a blob-free BL602 for the open source community to achieve a blob-free FOSS Bluetooth and WiFi on PINE64 devices, see Nutcracker Challenge: Blob-Free WiFi & BLE.

BL602 Specifications

BL602 Block Diagram.jpg



  • 128KB ROM
  • 276KB SRAM
  • 1Kb eFuse
  • 2MB Embedded Flash


  • Secure boot
  • Secure debug
  • AES 128/192/256
  • SHA-1/224/256
  • TRNG (True Random Number Generator)
  • PKA (Public Key Accelerator)


  • Wi-Fi 802.11 b/g/n
  • Bluetooth® Low Energy 5.0
  • Wi-Fi Fast connection with BLE assistance
  • Wi-Fi and BLE coexistence
  • Wi-Fi Security WPS/WEP/WPA/WPA2/WPA3
  • STA, SoftAP and sniffer modes
  • Multi-Cloud connectivity
  • 2.4 GHz RF transceiver
  • Integrated RF balun, PA/LNA

Package Type:

  • 32 pin QFN 4mm x 4mm

JTAG support:

  • See below for BL602 impact


Default JTAG pins

BL602 multiplexes four GPIO pins to provide the familiar JTAG lines. See the accompanying table for the default pin mappings.

These are the default JTAG pins in use after a cold boot. However, many pieces of software, including the demo that's installed by default on new PineCones, remap these pins to other functions. You cannot use the default wiring for JTAG while such software is running. This issue is especially prevalent on the PineCone because three of the default JTAG pins are connected to the onboard RGB LED. Nothing about the LED itself interferes with JTAG, but any program that uses the LED will necessarily remap some of the default JTAG pins to be GPIO.

The MaskROM download mode that the BL602 enters when you tie GPIO8 high does not remap the default JTAG pins, and so you can and should use that mode while checking basic functionality of your JTAG adapter.

Note that, just as software can remap the default JTAG pins to be something else, it can also remap other pins to be JTAG. Control over this is quite granular, with 5-6 candidate pins for each individual JTAG signal that can be mapped independently of one another. LEE Lup Yuen has written some sample code showing how to remap the JTAG pins so that your software can use the LED without giving up support for debugging.

Pine64 USB JTAG Adapter information and schematics

PineCone BL602 EVB information and schematics

The board layout

The approximate dimensions are 26mm x 43mm.

Schematics: PineCone BL602 EVB schematic ver 1.1

Note: In the PineCone revision 1.1 ("BL62B_EVB V1.1" silkscreened on back of board), CC1 and CC2 share one 5.1KΩ resistor. This means the board will fail to power when you use an e-marked USB-C cable like the one that comes with Apple chargers. See this article for details of why this happens. The next schematic design will give each line its own 5.1KΩ resistor as per the USB-C specification.

The board uses a CH340 Serial/USB adapter. This chip is commonly used in Arduino-class development boards. It is a full speed (12Mbps) USB interface and has vendor ID 0x1a86 with product ID 0x7523.

The GPIO pins (11, 12, 14, 17) plus the nearby RESET, POWER, and GND pins are all located on one side of the board, on J1 to provide JTAG connection.

Pinenut-01S Module information and schematics

Schematics and GPIO definitions:

The default firmware runs the UART at 2000000 bps. It will accept input whilst regularly outputting:

proc_hellow_entry: RISC-V rv32imafc
cur key status:1

Pinenut-12S Module information

GPIO definition: Pinenut-12S GPIO Definition ver 1.0

The onboard LED is connected to IO0

Datasheets for components and peripherals

Bouffalo BL-602 SoC information:

  • Bouffalo Lab's official bl_docs repository: should always contain the latest SoC documentation available, in PDF, HTML, and reStructuredText source forms.
  • PINE64's bl602-docs repository: contains an archive of all historical datasheets and reference manual PDFs but may lag behind Bouffalo's official repository. If you notice that it is, please submit a pull request!

USB/Serial adapter:

Misc notes

Planned to be available in at least three form factors:

  • NUT-01S -> ESP-01S
  • NUT-12S -> ESP-12S
  • NUT-15 -> RTL8723/AMPAK

Loading code

To load code, you must move the jumper to the position closest to the edge, press reset, load the code, move the jumper back toward the center of the board, and press reset again.

There are currently a number of loaders in progress, each with differing degrees of completeness and success on various operating systems.

  • In the build tree, there is BLFlashCube for Windows, which is a proprietary GUI for flashing images. Linux and macOS binaries are available via Bouffalo Lab's developer portal.
  • bl60x-flash is in Python and has been reported successful on MacOS catalina (10.15.6) by Punnerud and madushan1000.
  • BLOpenFlasher is a WIP, written in go, by Bouffalo Labs to provide source for a flash utility.
  • bl602tool is a Python utility in development.
  • Bouffalo's MCU tool (Mar 2021) Python image tool replaced both of the above. Now combined with eflash loader, deals with partitions, DTS, signing, fuses etc.
  • blflash serial flasher BL602 serial flasher, inspired by BLOpenFlasher

Development efforts

Articles and Blogs