From 6f22e249a43ee362e92e9bb920381400a261b5ea Mon Sep 17 00:00:00 2001 From: Kerogit Date: Sun, 11 May 2025 22:39:36 +0200 Subject: [PATCH] Documentation/platforms/avr: added information about UART usage This patch adds instructions on how to enable UART on AVR DA/DB chips Signed-off-by: Kerogit --- Documentation/platforms/avr/avrdx/index.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/Documentation/platforms/avr/avrdx/index.rst b/Documentation/platforms/avr/avrdx/index.rst index 644461ef5ee..4efb90e0277 100644 --- a/Documentation/platforms/avr/avrdx/index.rst +++ b/Documentation/platforms/avr/avrdx/index.rst @@ -81,6 +81,25 @@ highest speed. With baud rate 57600, performance was dependent on read/write buffer size. With buffer size of 8 there were still some missed bytes. +To be able to use standard serial driver, it is needed to enable +the peripheral in MCU-specific configuration in +:menuselection:`System Type --> AVR DA/DB Peripheral Selections` +UART peripherals are enabled using +:menuselection:`Enable serial driver for USARTn` options. When enabled, +additional option :menuselection:`Activate USART0 alternative pinout` +is provided. See the chip datasheet for pinout information. + +Other UART settings are then configured in driver configuration +:menuselection:`Device Drivers --> Serial Driver Support` +For every enabled peripheral, there is a corresponding +:menuselection:`USARTn Configuration` section. RTS/CTS and DMA support +must NOT be enabled here, neither of those is supported. + +Each enabled peripheral is automatically registered as ``/dev/ttySn`` +device file. File name corresponds to the peripheral related to it. +This for example means that ``USART1`` peripheral will always +be accessed through ``/dev/ttyS1`` regardless of what other ``USART`` +peripherals are enabled (if any.) Supported Boards ================