midi_uart_lib
Library for using Raspberry Pi Pico UART1 or both UART0 and UART1 for serial port MIDI.
If you need more that two serial port MIDI ports, or if you need two serial port MIDI ports and a stdio UART console, please consider using pio_midi_uart_lib instead.
Projects that use midi_uart_lib must install ring_buffer_lib in the same directory as this project. For example, if this project is installed in
lib/midi_uart_lib, then you must also install ring_buffer_lib
in the directory lib/ring_buffer_lib.
Projects that use midi_uart_libcontain a file called midi_uart_lib_config.h
that contains the following code
// The standard MIDI UART baud rate is 31250. If you want to do
// something special with the MIDI UART LIB, you can change this
#define MIDI_UART_LIB_BAUD_RATE 31250
See the midi2usbhost project for an
example of the midi_uart_lib_config.h file and for an example of how the library
is used.
It is up to the application that uses this library to "know" whether or not to
re-route or disable the stdio UART console (i.e pico_enable_stdio_uart in the CMakeLists.txt file) depending on which UART is used. In the Pico SDK, UART 0 is
the default stdio UART. The Pico SDK lets you change it to UART 1 or disable it completely. You must disable it completely if you use both UARTs for MIDI or
you will have problems. See the CMakeLists.txt file in the midi2usbhost project for an example of conditionally
disabling the stdio UART when UART 0 is used.
Also note that the UART TX pin for MIDI OUT is NOT open drain. For the projects I have tried, it has not mattered. Some have reported needing to insert a diode between the output pin and the MIDI OUT resistor to prevent poor signaling. If you are having issues due to the UART TX pin's active high output, please consider using pio_midi_uart_lib instead; the PIO code for the serial transmitter creates an open drain output.