Difference between revisions of "IoTGateway/BSP/Android/Gettingstarted/How to use UART for rk"

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== <span style="font-size: medium"><font color="#0066cc">RS-485</font></span> ==
 
== <span style="font-size: medium"><font color="#0066cc">RS-485</font></span> ==
  
RS-485 uses half-duplex communication, which means that one medium is shared for transmitting and receiving data. Therefore the system needs to control the RS-485 transceiver's transmit mode. Usually the UART RTS signal is used to switch the transmitter on and off. Our modules provide the following support:
+
RS-485 uses half-duplex communication, which means that one medium is shared for transmitting and receiving data. Therefore the system needs to control the RS-485 transceiver's transmit mode. Usually the UART RTS signal is used to switch the transmitter on and off.  
 
 
Enable the RS-485 feature by either using ioctrl ''TIOCSRS485'' from user space as described in [https://github.com/ADVANTECH-Corp/linux-imx6/blob/imx_4.1.15_1.0.0_ga/Documentation/serial/serial-rs485.txt <font color="#0066cc">RS-485 Kernel Documentation</font>].
 
  
 
= '''<span style="font-size: large"><span style="color: rgb(0, 0, 205)">Boards</span></span>''' =
 
= '''<span style="font-size: large"><span style="color: rgb(0, 0, 205)">Boards</span></span>''' =

Revision as of 05:25, 16 November 2017

Overview

The Android/Linux UART/serial port access from user is through the tty-devices. The tty-devices have different names depending on UART driver on different board.

RS-485

RS-485 uses half-duplex communication, which means that one medium is shared for transmitting and receiving data. Therefore the system needs to control the RS-485 transceiver's transmit mode. Usually the UART RTS signal is used to switch the transmitter on and off.

Boards

RSB4680 Borad

COM Name Device

RS485 support

COM1
/dev/ttyS2

COM2
/dev/ttyS4
Yes
COM3


COM4


COM5


COM6








 ROM3420 COM.png