UART is a ESP32 peripheral surface. It is for serial devices and, on some boards, explicit console routing. It is not part of the beginner Frothy beginner path.
Availability
The esp32_devkit_v1 board source exposes auxiliary UART bindings. The active
console itself is still special: it carries REPL input, output, and host
attachment.
Auxiliary UART
uart.init: (uart) (tx, rx, baud) -> Int
Creates an auxiliary UART handle.
aux is uart.init: UART_TX, UART_RX, 115200
uart.write: (uart) (byte, uart) -> nil
Writes one byte.
uart.write: 65, aux
uart.read: (uart) (uart) -> Int
Reads one byte.
uart.read: aux
uart.key?: (uart) (uart) -> Bool
Returns true when at least one byte is waiting.
when uart.key?: aux [
uart.read: aux
]
Console Routing
Boards that support console routing expose words for the active REPL transport:
console.info: (uart) () -> nil
Reports the current console route.
console.default: (uart) () -> nil
Returns the console to its default route.
console.uart!: (uart) (port, tx, rx, baud) -> nil
Moves the console to a selected UART route.
Use console-routing words carefully. If you move the REPL away from the host connection you are using, you can make the board appear unresponsive until you attach through the new route or reset to a safe state.