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Quick Summary 

This is a placeholder for notes and pics of 1-Wire stuff.

CMD_READ_SCRATCHPAD 

The following picture shows the 1-Wire Protocol for when the CMD_READ_SCRATCHPAD command is sent.

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 55, 28,FF,71,10,B2,17,01,FF, BE   (write)

Followed by:

 92,01,4B,46,7F,FF,0C,10,B5     (read)

Where:

 - 0xBE on the write-side is CMD_READ_SCRATCHPAD

 - 5th byte on the read side is SCRATCHPAD_CONFIG_REGISTER
        - 0x7F = TEMP_RESOLUTION_12_BIT

And here is the device id from the 1-Wire configuration:

ONEWIRE = {
  { Name='I0.OAt', id='FF0117B21071FF28', channel=1, slot=1 },
},

Result, pulse startup 

Heres a scope screenshot showing the reset pulse.

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Reset should be at least 480us. Master releases bus (goes high) Then Slave will take bus low for at least 60us.

Byte Written 

Screenshot showing a written byte.

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To read the byte written (think PIC acting in sniffer mode): - start clock on the falling edge - sample at about 30us (yes, micro seconds) - 18us will work, then its all same

Byte Read 

Screenshot showing a byte to read. This byte is written by the temp probe.

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To read the byte written: - start clock on the falling edge - sample at about 18us