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| 1 | | -* RS485 serial communications |
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| 2 | | - |
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| 3 | | -The RTS signal is capable of automatically controlling line direction for |
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| 4 | | -the built-in half-duplex mode. |
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| 5 | | -The properties described hereafter shall be given to a half-duplex capable |
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| 6 | | -UART node. |
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| 7 | | - |
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| 8 | | -Optional properties: |
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| 9 | | -- rs485-rts-delay: prop-encoded-array <a b> where: |
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| 10 | | - * a is the delay between rts signal and beginning of data sent in milliseconds. |
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| 11 | | - it corresponds to the delay before sending data. |
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| 12 | | - * b is the delay between end of data sent and rts signal in milliseconds |
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| 13 | | - it corresponds to the delay after sending data and actual release of the line. |
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| 14 | | - If this property is not specified, <0 0> is assumed. |
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| 15 | | -- rs485-rts-active-low: drive RTS low when sending (default is high). |
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| 16 | | -- linux,rs485-enabled-at-boot-time: empty property telling to enable the rs485 |
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| 17 | | - feature at boot time. It can be disabled later with proper ioctl. |
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| 18 | | -- rs485-rx-during-tx: empty property that enables the receiving of data even |
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| 19 | | - whilst sending data. |
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| 20 | | - |
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| 21 | | -RS485 example for Atmel USART: |
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| 22 | | - usart0: serial@fff8c000 { |
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| 23 | | - compatible = "atmel,at91sam9260-usart"; |
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| 24 | | - reg = <0xfff8c000 0x4000>; |
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| 25 | | - interrupts = <7>; |
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| 26 | | - atmel,use-dma-rx; |
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| 27 | | - atmel,use-dma-tx; |
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| 28 | | - linux,rs485-enabled-at-boot-time; |
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| 29 | | - rs485-rts-delay = <0 200>; // in milliseconds |
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| 30 | | - }; |
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| 31 | | - |
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| 1 | +See rs485.yaml |
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