hub.USB_VCP – USB_VCP

This class allows you to send and receive data from another device using USB.

class hub.USB_VCP(id=0)

Create a stream-like object representing the USB virtual comm port. It can be used to read and write data over USB to the connected host.

Only id=0 can be used.

init(flow=- 1) → None

Configures the USB VCP port.

Keyword Arguments

flow – Sets the flow control setting as a bitwise-or of USB_VCP.RTS (read behavior) and USB_VCP.CTS (write behavior). If this argument is -1, nothing happens.

setinterrupt(chr: int) → None

Sets the character which interrupts running Python code. This is set to 3 (CTRL-C) by default. When this character is received over the VCP port, a KeyboardInterrupt exception is raised.

Choose -1 to disable this interrupt. This is useful when you want to send raw bytes over the VCP port.

isconnected() → bool

Checks if there is an active connection.

Returns

True if connected, False if not.

any() → bool

Checks if characters are waiting to be read.

Returns

True if any characters are waiting, False if not.

close() → None

This method does nothing. It exists so that this object can act as a file.

read() → Optional[bytes]

read(nbytes: int) → Optional[bytes]

Reads data from the port in a non-blocking way.

Parameters

nbytes – How many bytes to read at most. If no value is given, it reads all available data.

Returns

The received bytes, or None if no pending data is available.

readinto(buf) → Optional[int]

readinto(buf, maxlen: int) → Optional[int]

Reads data from the port into an existing buffer in a non-blocking way.

Parameters

maxlen – How many bytes to read. At most min(maxlen, len(buf)) bytes will be read.

Returns

The number of bytes stored into buf, or None if no pending data is available.

readline() → Optional[bytes]

Reads a whole line from the serial device.

Returns

The data including the trailing newline character, or None if no pending data is available.

readlines() → list

Reads as much data as possible from the serial device and breaks it into lines.

Returns

Returns a list of bytes objects, each object being one of the lines. Each line includes the newline character. Returns an empty list if no pending data is available.

write(buf: bytes) → int

Writes the given bytes to the serial device.

Returns

The number of bytes written.

recv(data: Union[int, bytearray], timeout=5000) → int

Receives data on the bus.

Parameters

• data – Either an integer specifying the number of bytes to receive, or a mutable buffer, to be be filled with received bytes.

• timeout – Timeout in milliseconds to wait for the incoming data.

Returns

A new buffer with received bytes if data was an integer, or the number of bytes read into the buffer if a buffer was given.

send(data: Union[int, bytes], timeout=5000) → int

Send data on the bus.

Parameters

• data – An integer or buffer object to write.

• timeout – Timeout in milliseconds to wait for the data to be sent.

Returns

The number of bytes sent.

RTS = 1

CTS = 2