mkhuthir / radio

FM Radio using Si4703 chip

FM Radio using Silicon Labs Si4703 Chip

After cloning the repository don't forget to update the submodules (Si4703 and Nextion) using the following command:

git submodule update --init --recursive

Hardware used:

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• 1 x SparkFun FM Tuner Basic Breakout - Si4703 (https://www.sparkfun.com/products/11083)
• 1 x Arduino Pro Mini 328 - 3.3V/8MHz (https://www.sparkfun.com/products/11114)
• 1 x Rotary Encoder
• 1 x 2Ch Stereo Audio Amplifier
• 2 x 3W 4Ohm Speakers
• 1 x Nextion Display

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Connections:

Si4703 → 3.3V A.Pro Mini

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• GND → GND
• 3.3V → VCC
• SDIO → A.Pro Mini A4
• SCLK → A.Pro Mini A5
• SEN → NC * The breakout board has SEN pulled high
• RST → A.Pro Mini D4
• GPIO1 → LED2
• GPIO2 → A.Pro Mini D6

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Si4703 → Audio Amplifier

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• GND → GND
• ROUT → R-IN+
• LOUT → L-IN+

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Audio Amplifier → Speakers

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• R-OUT+ → R-SPK+
• R-OUT- → R-SPK-
• L-OUT+ → L-SPK+
• L-OUT- → L-SPK-

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3.3V A.Pro Mini

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• GND → GND
• VCC → 3.3V
• A4 → Si4703 SDIO
• A5 → Si4703 SCLK
• D6 → Si4703 GPIO2
• D2 → Rotary Encoder A
• D3 → Rotary Encoder B
• D4 → Si4703 RST
• D5 → LED1
• 10 → Nextion Display RX
• 11 → Nextion Display TX

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Rotary Encoder

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• A → A.Pro Mini D2
• B → A.Pro Mini D3
• C → GND

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LEDs

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• LED1 A → A.Pro Mini D5
• LED1 C → GND
• LED2 A → Si4703 GPIO1
• LED2 C → GND

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Nextion Display

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• RX → A.Pro Mini D10
• TX → A.Pro Mini D11
• +5V → +5V
• GND → GND

Description:

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This is example code can work with SparkFun FamFM radio kit and breadboard builds as per above connections. The used controller is Arduino Pro (3.3V, 8MHz) and has an FTDI header to load Arduino sketches. The hardware includes the Si4703 FM radio module to find the stations along with audio amps. and speakers for the audio. The circuit has a rotary encoder to tune the stations. The circuit displays the radio station over a serial terminal at 115200 and can be controlled from terminal. Also it saves the station settings on EEPROM and loads it in subsequent power ups.

Operation:

• The board must be powered with a switch mode 9V DC wall wart.
• Each click will increase/decrease station by 0.1MHz or 0.05MHz based in selected FM band range (US/EU, JP Wide, or JP)
• LEDs blink for every step