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@@ -1,9 +1,11 @@
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-# onewire Module
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+# 1-Wire Module
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+
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+This module provides functions to work with the [1-Wire](https://en.wikipedia.org/wiki/1-Wire) device communications bus system.
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## ow.check_crc16()
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-Compute the 1-Wire CRC16 and compare it against the received CRC.
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+Computes the 1-Wire CRC16 and compare it against the received CRC.
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-####Syntax
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+#### Syntax
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`ow.check_crc16(buf, inverted_crc0, inverted_crc1[, crc])`
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#### Parameters
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@@ -13,10 +15,10 @@ Compute the 1-Wire CRC16 and compare it against the received CRC.
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- `crc` CRC starting value (optional)
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#### Returns
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-`bool` true, if the CRC matches; false for mismatch.
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+true if the CRC matches, false otherwise
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## ow.crc16()
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-Compute a Dallas Semiconductor 16 bit CRC. This is required to check the integrity of data received from many 1-Wire devices. Note that the CRC computed here is **not** what you'll get from the 1-Wire network, for two reasons:
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+Computes a Dallas Semiconductor 16 bit CRC. This is required to check the integrity of data received from many 1-Wire devices. Note that the CRC computed here is **not** what you'll get from the 1-Wire network, for two reasons:
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1. The CRC is transmitted bitwise inverted.
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2. Depending on the endian-ness of your processor, the binary representation of the two-byte return value may have a different byte order than the two bytes you get from 1-Wire.
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@@ -25,98 +27,98 @@ Compute a Dallas Semiconductor 16 bit CRC. This is required to check the integr
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`ow.crc16(buf[, crc])`
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#### Parameters
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- - `buf` string value, data to be calculated check sum in string.
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- - `crc` CRC starting value (optional)
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+- `buf` string value, data to be calculated check sum in string
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+- `crc` CRC starting value (optional)
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#### Returns
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-`crc16` the CRC16, as defined by Dallas Semiconductor.
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+the CRC16 as defined by Dallas Semiconductor
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## ow.crc8()
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-Compute a Dallas Semiconductor 8 bit CRC, these are used in the ROM and scratchpad registers.
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+Computes a Dallas Semiconductor 8 bit CRC, these are used in the ROM and scratchpad registers.
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#### Syntax
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`ow.crc8(buf)`
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#### Parameters
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-`buf` string value, data to be calculated check sum in string.
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+`buf` string value, data to be calculated check sum in string
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#### Returns
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-CRC result as byte.
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+CRC result as byte
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## ow.depower()
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-Stop forcing power onto the bus. You only need to do this if you used the 'power' flag to `ow.write()` or used a `ow.write_bytes()` and aren't about to do another read or write.
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+Stops forcing power onto the bus. You only need to do this if you used the 'power' flag to `ow.write()` or used a `ow.write_bytes()` and aren't about to do another read or write.
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#### Syntax
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`ow.depower(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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`nil`
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####See also
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- - [ow.write()](#owwrite)
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- - [ow.write_bytes()](#owwrite_bytes)
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+- [ow.write()](#owwrite)
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+- [ow.write_bytes()](#owwrite_bytes)
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## ow.read()
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-Read a byte.
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+Reads a byte.
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####Syntax
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`ow.read(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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-Byte read from slave device.
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+byte read from slave device
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## ow.read_bytes()
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-Read multi bytes.
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+Reads multi bytes.
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#### Syntax
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`ow.read_bytes(pin, size)`
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#### Parameters
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- - `pin` 1~12, IO index
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- - `size` number of bytes to be read from slave device
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+- `pin` 1~12, I/O index
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+- `size` number of bytes to be read from slave device
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#### Returns
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`string` bytes read from slave device
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## ow.reset()
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-Perform a 1-Wire reset cycle.
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+Performs a 1-Wire reset cycle.
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#### Syntax
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`ow.reset(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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- - `1` if a device responds with a presence pulse.
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- - `0` if there is no device or the bus is shorted or otherwise held low for more than 250 µS.
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+- `1` if a device responds with a presence pulse
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+- `0` if there is no device or the bus is shorted or otherwise held low for more than 250 µS
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## ow.reset_search()
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-Clear the search state so that it will start from the beginning again.
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+Clears the search state so that it will start from the beginning again.
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#### Syntax
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`ow.reset_search(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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`nil`
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## ow.search()
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-Look for the next device.
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+Looks for the next device.
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#### Syntax
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`ow.search(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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`rom_code` string with length of 8 upon success. It contains the rom code of slave device. Returns `nil` if search was unsuccessful.
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@@ -125,14 +127,14 @@ Look for the next device.
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[ow.target_search()](#owtargetsearch)
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## ow.select()
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-Issue a 1-Wire rom select command. Make sure you do the `ow.reset(pin)` first.
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+Issues a 1-Wire rom select command. Make sure you do the `ow.reset(pin)` first.
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#### Syntax
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`ow.select(pin, rom)`
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#### Parameters
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- - `pin` 1~12, IO index
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- - `rom` string value, len 8, rom code of the salve device
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+- `pin` 1~12, I/O index
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+- `rom` string value, len 8, rom code of the salve device
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#### Returns
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`nil`
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@@ -195,38 +197,38 @@ end
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[ow.reset()](#owreset)
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## ow.setup()
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-Set a pin in onewire mode.
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+Sets a pin in onewire mode.
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#### Syntax
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`ow.setup(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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`nil`
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## ow.skip()
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-Issue a 1-Wire rom skip command, to address all on bus.
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+Issues a 1-Wire rom skip command, to address all on bus.
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#### Syntax
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`ow.skip(pin)`
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#### Parameters
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-`pin` 1~12, IO index
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+`pin` 1~12, I/O index
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#### Returns
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`nil`
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## ow.target_search()
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-Set up the search to find the device type `family_code`. The search itself has to be initiated with a subsequent call to `ow.search()`.
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+Sets up the search to find the device type `family_code`. The search itself has to be initiated with a subsequent call to `ow.search()`.
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#### Syntax
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`ow.target_search(pin, family_code)`
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#### Parameters
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- - `pin` 1~12, IO index
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- - `family_code` byte for family code
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+- `pin` 1~12, I/O index
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+- `family_code` byte for family code
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#### Returns
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`nil`
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@@ -235,15 +237,15 @@ Set up the search to find the device type `family_code`. The search itself has t
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[ow.search()](#owsearch)
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## ow.write()
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-Write a byte. If `power` is 1 then the wire is held high at the end for parasitically powered devices. You are responsible for eventually depowering it by calling `ow.depower()` or doing another read or write.
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+Writes a byte. If `power` is 1 then the wire is held high at the end for parasitically powered devices. You are responsible for eventually depowering it by calling `ow.depower()` or doing another read or write.
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#### Syntax
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`ow.write(pin, v, power)`
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#### Parameters
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- - `pin` 1~12, IO index
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- - `v` byte to be written to salve device
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- - `power` 1 for wire being held high for parasitically powered devices
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+- `pin` 1~12, I/O index
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+- `v` byte to be written to salve device
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+- `power` 1 for wire being held high for parasitically powered devices
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#### Returns
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`nil`
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@@ -252,15 +254,15 @@ Write a byte. If `power` is 1 then the wire is held high at the end for parasiti
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[ow.depower()](#owdepower)
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## ow.write_bytes()
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-Write multi bytes. If `power` is 1 then the wire is held high at the end for parasitically powered devices. You are responsible for eventually depowering it by calling `ow.depower()` or doing another read or write.
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+Writes multi bytes. If `power` is 1 then the wire is held high at the end for parasitically powered devices. You are responsible for eventually depowering it by calling `ow.depower()` or doing another read or write.
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#### Syntax
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`ow.write_bytes(pin, buf, power)`
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#### Parameters
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- - `pin` 1~12, IO index
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- - `buf` string to be written to slave device
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- - `power` 1 for wire being held high for parasitically powered devices
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+- `pin` 1~12, IO index
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+- `buf` string to be written to slave device
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+- `power` 1 for wire being held high for parasitically powered devices
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#### Returns
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`nil`
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