Si4844 Library for Arduino

This Arduino library was developed to work with the SI4822, SI4826, SI4827, SI4840, 4844A, and 4844B "BROADCAST ANALOG TUNING DIGITAL DISPLAY AM/FM/SW RADIO RECEIVER" devices. It is available on Arduino IDE. This library is intended to provide an easier interface to control the SI48XX family. When appropriate, this documentation will use the acronym SI48XX to refer to the following devices: SI4822, SI4826, SI4827, SI4840, SI4844A, and SI4844B. In most cases, references to the SI4844 device also apply to the other aforementioned devices.

The SI48XX, along with other devices in its family, provides the ideal combination of analog tuning and digital interface, enabling the development of receivers reminiscent of the iconic models from the 1970s and 1980s. These classic receivers featured visual interfaces using liquid crystal displays or LEDs, offering a unique and nostalgic user experience. Therefore, a notable application for the SI48XX is the construction of a vintage-style receiver that blends retro aesthetics with modern technology.

A less common application, but one that might catch the attention of some hobbyists, is the conversion of receivers based on the SI4825, which feature mechanical tuning and only an analog dial, into a receiver based on the SI4827. This model retains the same characteristics as the SI4825 but adds a digital interface through a display. This video shows that idea: Improving a Si4825-based radio with the Si4827 and Arduino.

It is important to highlight that the analog tuning of this device does not offer the same experience as the classic receivers with variable capacitor tuning. However, depending on how you configure your electronic project, the quality of the 100K potentiometer used for mechanical tuning, and the firmware, you might be pleasantly surprised by the results.

Use the 'Content Index' of this documentation and the example sketches, especially SI4844_00_POC.ino, to make the most of this library.

This library can be freely distributed using the MIT Free Software model. Copyright (c) 2019 Ricardo Lima Caratti

Contact: pu2clr@gmail.com

By Ricardo Lima Caratti, Oct 2019.

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. License Copyright
2. Your support is important
3. About the SI4844 Architecture
4. Terminology
5. Library Features
6. Library Installation
7. Hardware Requirements and Setup
   • Schematic
   • Component Parts
   • Photos
8. API Documentation
9. References
10. Source code - Arduino Examples
11. Videos

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See also

• PU2CLR Si4735 Library for Arduino. This library was built based on “Si47XX PROGRAMMING GUIDE; AN332” and it has support to FM, AM and SSB modes (LW, MW and SW). It also can be used on all members of the SI47XX family respecting, of course, the features available for each IC version;
• PU2CLR SI4844 Arduino Library. This is an Arduino library for the SI4844, BROADCAST ANALOG TUNING DIGITAL * DISPLAY AM/FM/SW RADIO RECEIVER, IC from Silicon Labs. It is available on Arduino IDE. This library is intended to provide an easier interface for controlling the SI4844.
• PU2CLR AKC695X Arduino Library. The AKC695X is a family of IC DSP receiver from AKC technology. The AKC6955 and AKC6959sx support AM and FM modes. On AM mode the AKC6955 and AKC6959sx work on LW, MW and SW. On FM mode they work from 64MHz to 222MHz.
• PU2CLR KT0915 Arduino Library. The KT0915 is a full band AM (LW, MW and SW) and FM DSP receiver that can provide you a easy way to build a high quality radio with low cost.
• PU2CLR BK108X. The BK1086 and BK1088 are DSP receivers from BAKEN. The BK1088 is a BROADCAST FM and AM (LW, MW and ) RECEIVER and BK1086 is a subset of the BK1088 (it does not have LW and SW acording to the Datasheet).
• PU2CLR RDA5807 Arduino Library. The RDA5807 is a FM DSP integrated circuit receiver (50 to 115MHz) with low noise amplifier support. This device requires very few external components if compared with other similar devices. It also supports RDS/RBDS functionalities, direct auto gain control (AGC) and real time adaptive noise cancellation function.
• PU2CLR SI470X Arduino Library. It is a Silicon Labs device family that integrates the complete functionalities for FM receivers, including RDS (Si4703).
• PU2CLR MCP23008. It is an Arduino Library to control the MCP23008/MCP23S08 8-Bit I/O Expander. The MCP23008 device provides 8-bit, general purpose, parallel I/O expansion. It can be controlled via I2C bus applications. It is a great and inexpensive device that allow you to add more devices to be controlled by your Arduino board via I2C protocol.
• PU2CLR - PCF8574 Arduino Library. It is an Arduino Library to control the PCF8574 8-Bit I/O Expander. The PCF8574 device provides 8-bit, general purpose, parallel I/O expansion. It can be controlled via I²C bus applications. It is a great and inexpensive device that allow you to add more peripherals to be controlled by your Arduino board via I²C protocol.
• QN8066 FM DSP RX/TX Arduino Library. An easy-to-use interface for controlling the QN8066 FM transceiver and receiver.

More Arduino Projects developed by author

• Multipurpose signal generator with SI5351. It is a multipurpose signal generator controlled by Arduino. This project uses the SI5351 from Silicon Labs. The Arduino sketch is configured to control the SI5351 with three channels from 32.768KHz to 160MHz and steps from 1Hz to 1MHz.
• Shortwave Arduino Transmitter. This project is about a shortwave transmitter from 3 MHz to 30 MHz. It uses the SI5351 oscillator from Silicon Labs controlled by Arduino. Also, you can use it with a crystal oscillator. In this case, you will not need the SI5351 device and Arduino.
• Android and iOS Bluetooth Remote Control for PU2CLR Arduino Library DSP receivers. This project is an extension of the Arduino library projects for: SI4735; AKC6959 and KT0915. It is a simple example that shows a way to use your smartphone as a remote control via Bluetooth. In order to follow the steps presented here, I am assuming that you have some knowledge in development for mobile devices. Also, you will need to be familiar with the Javascript programming language. The development environment used by this project is the Apache Cordova. Cordova is a open-source mobile development framework that allows you to develop cross-platform applications. That means you can code once and deploy the application in many system, including iOS and Android. Cordova provides an easy way to develop for iOS and Android.
• Band Pass Filter controlled by Arduino. It is a HF band pass filter controlled by Arduino. It is designed for HF receivers. With this project, you can use a set of up to four HF bandpass filters that can be selected by Arduino. To do that you will need just two digital Arduino pins.

Important

The SI48XX (SI4822, SI4826, SI4827, SI4840, 4844A, and 4844B) is a 3.3V part. If you are not using a 3.3V version of Arduino, you have to use a kind of 5V to 3.3V converter. See Hardware Requirements and Setup.

A good alternative to the Arduino Uno or Arduino Nano for a project using the SI48XX device is a board based on the LGT8F328 microcontroller. This device offers excellent compatibility with the Ardui