Nt1310 Unit 8 Assignment 1
High-level Design:
This project used an Atmega644 microcontroller clocked at 20MHz in each of the two functional modules for processing. Memory storage is provided by a standard Secure Digital (SD) card. Xbee modules provide bidirectional wireless communication and we use the TLV5616 DAC chip for generating analog audio. The LM358 dual op amp provides active filtering to the output of the DAC. Music files can be added to the SD card using any computer with a multimedia card reader. Once the base station detects an SD card inserted into the holder, it awaits data requests from the portable module. The portable module requests data when required and feeds these values into the DAC. The DAC output is low-pass filtered by the op amp, which also buffers the DAC output before it reaches the audio output …show more content…
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1. Microcontroller Board - The standard 4760 prototyping board pictured above is populated with an Atmega644 microcontroller clocked at 20 MHz. The serial transceiver and DB-9 connector have been soldered on for debugging purposes. They remain unused in the final implementation. The board accepts a 9-12 V input and regulates it down to 5 V for the on board microcontroller. A 0.1 inch header has been soldered into the row of breakout vias along one edge to allow it to plug directly into a breadboard. The onboard programming header allows in-situ reprogramming of the microcontroller's flash.
2. Pushbuttons - The row of four push buttons visible in the photograph above allow the user to control music playback. One side of each button is connected to ground while the other connects to a GPIO pin on the microcontroller. A button press causes the appropriate microcontroller pin to read a low instead of a high, registering a possible button
This project used an Atmega644 microcontroller clocked at 20MHz in each of the two functional modules for processing. Memory storage is provided by a standard Secure Digital (SD) card. Xbee modules provide bidirectional wireless communication and we use the TLV5616 DAC chip for generating analog audio. The LM358 dual op amp provides active filtering to the output of the DAC. Music files can be added to the SD card using any computer with a multimedia card reader. Once the base station detects an SD card inserted into the holder, it awaits data requests from the portable module. The portable module requests data when required and feeds these values into the DAC. The DAC output is low-pass filtered by the op amp, which also buffers the DAC output before it reaches the audio output …show more content…
Click within an area to view details about that circuit.
1. Microcontroller Board - The standard 4760 prototyping board pictured above is populated with an Atmega644 microcontroller clocked at 20 MHz. The serial transceiver and DB-9 connector have been soldered on for debugging purposes. They remain unused in the final implementation. The board accepts a 9-12 V input and regulates it down to 5 V for the on board microcontroller. A 0.1 inch header has been soldered into the row of breakout vias along one edge to allow it to plug directly into a breadboard. The onboard programming header allows in-situ reprogramming of the microcontroller's flash.
2. Pushbuttons - The row of four push buttons visible in the photograph above allow the user to control music playback. One side of each button is connected to ground while the other connects to a GPIO pin on the microcontroller. A button press causes the appropriate microcontroller pin to read a low instead of a high, registering a possible button