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-------------------------------------------------------------------------------
Dallas DS1985 16kbit Add-Only iButton
-------------------------------------------------------------------------------

This is a set of example captures of the 1-Wire traffic from a
Dallas DS1985 iButton device.

This specific iButton device has a registration number of 0x05000000586ce20b
(family code: 0x05, serial number: 0x000000586ce2, CRC: 0x0b).

The device has the following markings:

  Dallas
  0050 Registered B1 
  05  0B
  000000586CE2
  DS1985-F5

The "1-Wire/iButton Drivers for Windows" 4.03 software was used with a
Maxim DS9097U-E25 serial port 1-Wire interface adapter (which itself
contains a Maxim DS2480B serial 1-Wire line driver chip).
The DS9097U-E25 was attached to a PC using a USB-to-serial adapter.

The following information can be seen in the Windows software for the
respective dumps (when clicking on the respective tabs/entries):

Polling:

 - The Windows software was configured as follows:
   - Device poll rate: 1 second
   - 1-Wire search mode: Show normal devices

Main memory:

 - Contents: all-0xff (pages 0 - 63, each page 32 bytes in size)
 - Start address: 0
 - Bank size: 2048 bytes
 - General-purpose/non-volatile/read-only/read-write/write-once: Y/Y/N/N/Y

Write protect pages:

 - Contents: ff ff ff ff ff ff ff ff
 - Start address: 0
 - Bank size: 8 bytes
 - General-purpose/non-volatile/read-only/read-write/write-once: N/Y/N/N/Y

Write protect redirection:

 - Start address: 0x20
 - Bank size: 8 bytes
 - General-purpose/non-volatile/read-only/read-write/write-once: N/Y/N/N/Y

Bitmap of used pages for file structure:

 - Start address: 0x40
 - Bank size: 8 bytes
 - General-purpose/non-volatile/read-only/read-write/write-once: N/Y/N/N/Y

Page redirection bytes:

 - Contents: all-0xff (pages 0 - 3, each page 16 bytes in size)
 - Start address: 0x100
 - Bank size: 64 bytes
 - General-purpose/non-volatile/read-only/read-write/write-once: N/Y/N/N/Y

Details:
https://en.wikipedia.org/wiki/1-Wire
http://www.maxim-ic.com/datasheet/index.mvp/id/2827/t/al
http://www.maxim-ic.com/app-notes/index.mvp/id/192
http://www.maxim-ic.com/datasheet/index.mvp/id/2983/t/al
http://www.maxim-ic.com/app-notes/index.mvp/id/192


Logic analyzer setup
--------------------

The logic analyzer used was a Saleae Logic (at 8MHz):

  Probe       DS2480B pin
  -----------------------
  1 (black)   1-W

The sigrok command line used was:

  sigrok-cli -d fx2lafw:samplerate=8mhz --time 5s -p 1=OWR -o <file>