Implementation of a composite USB device containing a CDC interface and a audio MIDI interface based on examples from Microchip Libraries for Application (MLA). It works as a bridge. Every packet that comes from one interface goes to the other.
- Device: PIC18F2550 or PIC18F4550
- IDE: MPLAB X IDE v5.30
- Compiler: XC8 v2.10
- Written in C 90 standard
I tried to modify as little as possible the examples provided by MLA, but the structure is quite messy.
Before programming a device, check the files bsp/leds.c and bsp/buttons.c to configure the right GPIOs.
app_device_cdc_basic.c contains the main task for the CDC interface.
app_device_audio_midi.c contains the main task for the MIDI interface. Also, if BUTTON_DEVICE_AUDIO_MIDI is pressed, generates a MIDI packet.
app_led_usb_status.c contains the status LED update task to reflect the status of the USB connection.
If you're looking for a descriptor for the composite device is located at usb/usb_descriptors.c.