RS485 Communication problem in BeagleBone Black

I am trying to send and receive data from my PC to BeagleBone Black via RS485. I used a 'ISO3082' transceiver in between to make the signals compatible. I used UART2 of BBB. The RE/DE pin is not getting toggled for Tx and Rx. My dts code is as below:

&am33xx_pinmux { uart2_pins: pinmux_uart2_pins {         pinctrl-single,pins = <                 0x154 (PIN_OUTPUT_PULLDOWN | MUX_MODE1)/* P9_21: uart2_txd */                 0x150 (PIN_INPUT_PULLUP | MUX_MODE1)   /* P9_22: uart2_rxd */                 0x04c (PIN_INPUT_PULLDOWN  | MUX_MODE7) /*P9_16: gpio1[19] */                 >;         };  }; };  &uart2 {        status = "okay";        pinctrl-names = "default";        pinctrl-0 = <&uart2_pins>;        rts-gpio = <&gpio1 19 GPIO_ACTIVE_HIGH>;        rs485-rts-active-high;        /* rs485-rx-during-tx; */        rs485-rts-delay = <1 1>;        linux,rs485-enabled-at-boot-time;      }; 

No data transfer is happening. What may have gone wrong?

uname -a Linux arm 4.1.15-ti-rt-r40 #1 SMP PREEMPT RT Fri Jan 8 09:44:57 UTC 2016 armv7l armv7l armv7l GNU/Linux 


Category: uart Time: 2016-07-28 Views: 0
Tags: uart

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