PU2CLR BK108X Arduino Library

The BK1088E is a single-chip solution for receiving AM, FM, and shortwave radio. Using inexpensive components (Arduino Pro Mini, some push buttons, and a standard OLED or TFT display), the hobbyists can build serviceable little receiver based on BK1088E with impressive performance.

This project involves a cross-platform Arduino Library designed to control the BK1086 and BK1088 devices. The BK108X Arduino Library is based on the documentation titled "BK1086/88E BROADCAST AM/FM/SW/LW RADIO RECEIVER; Rev.1.4" provided by BEKEN Corporation. Its purpose is to enable seamless control and integration of the BK1086 and BK1088 devices within Arduino projects.

This library can be freely distributed using the MIT Free Software model.

Copyright (c) 2020 Ricardo Lima Caratti.

Contact: pu2clr@gmail.com.

Donate

If you find this project useful, consider making a donation so that the author of this library can purchase components and modules for improvements and testing of this library. Click here to donate.

About Me

I hold a Master's degree in Educational Technology from the Federal University of Ceará, where I delved into the ways technology can enhance learning experiences. My passion for computer science led me to specialize in it, focusing on Distributed Systems Development with an Object-Oriented approach, at the University of Brasília. My academic journey began with a Bachelor's degree in Information Systems from the União Pioneira de Integração Social (UPIS-Brasília). Outside the classroom, my main hobbies are electronics and Amateur Radio.

Contents

1. Preface
2. BK1086/88E features
3. Library Installation
4. API Documentation
5. Functional Block Diagram
6. BK1086/88E TSSOP20 pinout
7. Schematic
8. Sketch examples
9. Videos
10. References

Preface

At the end of 2019, I embarked on several Arduino library development projects aimed at controlling DSP receivers. The initial endeavor involved creating an Arduino library for the SI4844, followed by libraries for the Si473X family, all manufactured by Silicon Labs. The positive reception and enthusiasm from radio listeners, experimenters, and hobbyists regarding the use of these libraries prompted me to expand my efforts.

As a result, I developed additional libraries for the AKC695X, KT0915, SI470X, and RDA5807, catering to the Arduino IDE platform. While researching the BK1086/88 Datasheet, I realized its suitability for radio enthusiasts and hobbyists. Initially, I found limited documentation available compared to the previously mentioned devices. This motivated me to gather as much information as possible about the BEKEN family of devices.

I reached out to BEKEN Corporation to request information about the BK1086/88E, and I am grateful for their prompt response and attention. I would like to extend my sincere appreciation to BEKEN Corporation for their cooperation and assistance in this endeavor.

This library is based on the BEKEN manual “BK1086/88 - BROADCAST AM/FM/SW/LW RADIO RECEIVER REV1.3” provided by BEKEN Corporation and experiments made by me during the development process.

If you are a hobbyist, a radio enthusiast and enjoy Arduino, this project is for you.

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All Band receiver with BK1088E and LilyGo panel

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BK1088E FM, AM (LW, MW and SW) DSP receiver working with Arduino

MIT License

Copyright (c) 2019 Ricardo Lima Caratti

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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Thanks

Mr. Peng Roy, from BEKEN Corporation, for providing me with the technical information on the BK1086/88.

Your support is important

If you have suggestions to improve this project, please let me know.

BK1086/88 features

Main features

1. Worldwide 64~108 MHz FM band support;
2. Worldwide 520~1710kHz AM band support;
3. LW band support(153-279kHz,BK1088E only)
4. SW band support(2.3-21.85MHz, BK1088E only);
5. Automatic gain control(AGC);
6. Automatic frequency control(AFC);
7. Digital FM stereo decoder;
8. Automatic FM stereo/mono blend;
9. Automatic noise suppression;
10. 50us/75us de-emphasis;
11. RDS/RBDS decoder;
12. 2.4 ~ 5.5 V supply voltage;
13. Wide range reference clock support;
14. 32.768KHz crystal oscillator.

Useful information

• BK1086/88 can be controlled by an MCU through 2-wire I2C mode.
• The BK1088 already comes with 40K internal pull-up resistors on the i2c bus. Probably, no external pull-up resistors will be needed. However, depending on the size of the bus, consider using external pull-up resistors;
• BK1086/88 has an internal automatic tuning technology, which can automatically adjust the internal variable capacitance value to make the resonant circuit in the best resonance state at the current operating frequency, thus greatly simplifying the front-end design;
• BK1086 only supports FM and medium wave, BK1088 supports short wave and long wave in addition to FM and medium wave;

Library Installation

You can install this library on your Arduino environment using different methods.

Installing via Arduino IDE

This library is available on Arduino IDE platform. This video will show you how to install the Arduino Library for the BK1086 / 88 DSP device on your local computer.

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Installing via the repository

With this approach, you will have the most current version of the library. However, it may not be the most stable version. This is because the current version is always in development. Prefer releases. Do you need some old version (release) of this library? If yes, check here.

To install the current version, you have to download this library in zip format. After, unzip the BK108X-master.zip file in your Arduino Library folder.

• On Windows: "My Documents\Arduino\libraries"
• On MAC OS: ˜/Documents/Arduino/libraries
• On Linux: ˜/Arduino/libraries

Functional Block Diagram

Source: "BK1086/88E BROADCAST AM/FM/SW/LW RADIO RECEIVER; Rev.1.3; page 3"

BK1086/88E TSSOP20 pinout

Source: "BK1086/88E BROADCAST AM/FM/SW/LW RADIO RECEIVER; Rev.1.3; page 23"

| Pin Number | Name | Description | | ---------- | -------- | ----------- | | 1 | GND | Ground. Connect to ground plane on PCB | | 2 | GND | Ground. Connect to ground plane on PCB | | 3 | FMI | FM RF input | | 4 | RFGND | RF ground | | 5 | AMI | MW/SW/LW RF input | | 6 | GND | Ground. Connect to ground plane on PCB | | 7 | SCLK | Clock for Serial communications | | 8 | SDIO | Serial data input/output | | 9 | RCLK | 32.768kHz - 38.4MHz external reference clock input/32.768KHz Oscillator input | | 10 | VDD | Power supply for digital and I/O | | 11 | ROUT | Right audio output | | 12 | LOUT | Left audio output | | 13 | VA | Power supply for analog | | 14 | GPIO3 | General purpose output 3 | | 15 | GPIO2 | General purpose output 2 | | 16 | EXTLNA | External LNA control | | 17 | RIN2 | Line in input (Right channel2) | | 18 | LIN2 | Line in input (Left channel2) | | 19 | RIN1 | Line in input (Right channel1) | | 20 | LIN1 | Line in input (Left channel1) |

Schematic

BEKEN Typical Application Schematic

The image below was extracted from "BK1086/88E BROADCAST AM/FM/SW/LW RADIO RECEIVER; Rev.1.3; page 25". It is a basic circuit suggested by BEKEN.

BK1088E(SSOP20) and Arduino Schematic

The schematic provided below is based on the typical appl