| 1 | * RS485 serial communications |
| 2 | |
| 3 | The RTS signal is capable of automatically controlling line direction for |
| 4 | the built-in half-duplex mode. |
| 5 | The properties described hereafter shall be given to a half-duplex capable |
| 6 | UART node. |
| 7 | |
| 8 | Required properties: |
| 9 | - rs485-rts-delay: prop-encoded-array <a b> where: |
| 10 | * a is the delay between rts signal and beginning of data sent in milliseconds. |
| 11 | it corresponds to the delay before sending data. |
| 12 | * b is the delay between end of data sent and rts signal in milliseconds |
| 13 | it corresponds to the delay after sending data and actual release of the line. |
| 14 | |
| 15 | Optional properties: |
| 16 | - linux,rs485-enabled-at-boot-time: empty property telling to enable the rs485 |
| 17 | feature at boot time. It can be disabled later with proper ioctl. |
| 18 | - rs485-rx-during-tx: empty property that enables the receiving of data even |
| 19 | whilst sending data. |
| 20 | |
| 21 | RS485 example for Atmel USART: |
| 22 | usart0: serial@fff8c000 { |
| 23 | compatible = "atmel,at91sam9260-usart"; |
| 24 | reg = <0xfff8c000 0x4000>; |
| 25 | interrupts = <7>; |
| 26 | atmel,use-dma-rx; |
| 27 | atmel,use-dma-tx; |
| 28 | linux,rs485-enabled-at-boot-time; |
| 29 | rs485-rts-delay = <0 200>; // in milliseconds |
| 30 | }; |
| 31 | |