This makes the CDC "Serial" object on the Leonardo and similar boards
support this recently introduced method as well. The CDC code in the sam
core is not changed.
This allows detecting when the USB host sends a break request and what
the value of the request was. See the comments in USBAPI.h for details.
This just modifies the avr core, not the sam core.
This allows a sketch to find out the settings chosen by the USB host
(computer) and act accordingly.
Other than reading the DTR flag and checking if the baudrate is 1200,
the regular CDC code doesn't actually use any of these settings.
By exposing these settings to the sketch, it can for example copy them
to the hardware UART, turning the Leonardo into a proper USB-to-serial
device. This can be useful to let the computer directly talk to whatever
device is connected to the hardware serial port (like an XBee module).
The Teensy core already supported these methods. This code was
independently developed, but the method names were chosen to match the
Teensy code, for compatibility (except that `dtr()` and `rtr()` return
`bool`, while the Teensy version return a `uint8_t`).
This change is applied to both the avr and sam cores, which have a very
similar CDC implementation.
Before, this decision was made in few different places, based on
sometimes different register defines.
Now, HardwareSerial.h decides wich UARTS are available, defines
USE_HWSERIALn macros and HardwareSerial.cpp simply checks these macros
(together with some #ifs to decide which registers to use for UART 0).
For consistency, USBAPI.h also defines a HAVE_CDCSERIAL macro when
applicable.
For supported targets, this should change any behaviour. For unsupported
targets, the error messages might subtly change because some checks are
moved or changed.
Additionally, this moves the USBAPI.h include form HardareSerial.h into
Arduino.h and raises an error when both CDC serial and UART0 are
available (previously this would silently use UART0 instead of CDC, but
there is not currently any Atmel chip available for which this would
occur).
Mostly useful for Leonardo - simple way to test whether the port is actually opened by an application and ready to receive data. For Serial objects attached to real UARTs always returns true.
This fixes the issue Federico reported where bytes written by host but not read by sketch would cause serial connection to lock up. Ring buffer implementation is based on HardwareSerial.cpp.
Adds public accept() method to CDC.
Nico
Cristian Maglie
Peter Van Hoyweghen
Matthijs Kooijman
Martino Facchin
Cristian Maglie
Embedded Micro
Paul Brook
Justin Rajewski
David A. Mellis
Zach Eveland