Do you have the idea to create a USB sound card, which is based on a PIC interface? Today, you have the chance to learn to develop an USB Audio Streamer V1.0, or it is a microchip PIC based USB sound card.
For this project, the hardware part is based on all Microchip, and the software part uses a modified version of Microchip USB framework. The main objective of this custom interface is for programming the device serial number and upgrading the firmware.
The Microchip PIC18F2550 USB processor is used as the sound card purpose. The processor is clocked at 48MHz, where it is the maximum rate for this processor. The microcontroller is being connected via the SPI port to the Microchip MCP4822 12bit D/A converter. The separate port is being used in the project to control the volume and enable it to run inside the processor at a different priority level.
The main software part that consist in the USB audio streamer are the audio card firmware, the card INF file for the custom interface, a C++ library and a command line utility. You can simply download the source code here.
Hope you guys will enjoy this project!