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Maxim Integrated DS2432 1k-Bit Protected 1-Wire EEPROM with SHA-1 Engine
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This is a set of example captures of the 1-Wire traffic from a Maxim Integrated
(previously Dallas Semiconductor) DS2432 1k-Bit Protected 1-Wire EEPROM with
SHA-1 Engine.

Details:
http://datasheets.maximintegrated.com/en/ds/DS2432.pdf
http://pdf.datasheetcatalog.com/datasheet/maxim/DS2432.pdf


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

The logic analyzer used was a MCU123 Saleae Logic clone:

  Channel       DS2432 pin
  ------------------------
  1 (OWR)       1 (1-WIRE)

sigrok-cli was used to capture the trace with the following parameters:

  - sample rate: 1 MHz
  - samples: 1 M
  - trigger: falling channel 1 (OWR)

  sigrok-cli --driver fx2lafw --channels D0=OWR --config samplerate=1m \
             --samples 1M --triggers OWR=f --output-file ds2432.sr


ds2432.sr
---------

The DS2432 chip in TSOC 6 package has the same following top marking:
  DS
  2432
  618B1

And bottom marking:
  32AC

The communication is initiated by a Bus Pirate HW v3b FW v6.6 in 1-Wire mode.

The Bus Pirate in 1-Wire (master) mode performs the following actions:

  - Read ROM ID using "READ ROM" ROM command (0x33): `(51)`

  - Write scratchpad with 0's at target address 0x80 (secret memory) and read
    resulting CRC using "Write Scratchpad" function command (0x0Fh):
    `[0xcc 0x0f 0x80 0 0:8 r:2`

  - Read target address, status byte, scratchpad, CRC using "Read Scratchpad"
    function command (0xAA): `[0xcc 0xaa r:3 r:8 r:2`

  - Provide authentication pattern store secret from scratchpad to memory and
    read result after 10 ms using "Load First Secret" function command (0x5A):
    `[0xcc 0x5a 0x80 0x00 0x5F %:10 r`

  - Read authentication pattern using "Read Scratchpad" function command
    (0xAA): `[0xcc 0xaa r:3`

  - Copy scratchpad to memory with erroneous MAC and read result after 10 ms
    using "Copy Scratchpad" function command (0x55):
    `[0xcc 0x55 0x80 0x00 0xDF 0x42:20 %:10 r`

  - Read first 8 bytes starting at target address 0 using "Read Memory"
    function command (0xF0): `[0xcc 0xf0 0 0 r:8`

  - Read page 0 and authentication using "Read Authenticated Page" function
    command (0xa5): `[0xcc 0xa5 0 0 r:32 r:1 r:2 %:2 r:20 r:2`

  - Compute next secret using memory page 0 and read result after 12 ms using
    "Compute Next Secret" function command (0x33): `[0xcc 0x33 0x00 0x00 %:12 r`

  - Read scratchpad to verify result: `[0xcc 0xaa r:3 r:8 r:2`