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-------------------------------------------------------------------------------
Avago ADNS-5020
-------------------------------------------------------------------------------

This directory contains a capture of the communication between a Cypress
CY7C63813 and an Avago ADNS-5020 optical mouse sensor.

This is the internals of a fairly generic Dell optical mouse.

It is not nearly a complete sample of what types of traffic are possible,
specifically, it doesn't include a capture of "Burst Mode" traffic, which the
mouse firmware doesn't appear to use, even though Avago "highly recommends"
that burst mode be used for all devices.


adns5020-cy7c63813_init.sr
--------------------------

Captures the traffic from power on of the device (USB plug in) for 1 second.
Traces the initialization and reset pins as well as some general traffic.


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

The logic analyzer used was a generic Saleae Logic clone (at 6MHz).

Avago documents max speed as 1MHz. 6MHz is used to try and avoid catching
any glitches on CS.

  Probe  Pin     Description
  --------------------------
  0      VDD     Used to trigger sampling
  3      SDIO    Bidir, but we use the MOSI stack from SPI
  4      SCK     SPI clock
  5      NCS     Chip select
  6      NRESET  Chip reset
  7      XY_LED  Chip LED control, not used by this configuration


Data
----

The sigrok command line used was:

  sigrok-cli -d fx2lafw --config samplerate=6M --time 1s \
             -o adns5020-cy7c63813_init.sr -t VDD=r \
             --channels 3=SDIO,5=NCS,4=SCK,6=NRESET,7=XY_LED,0=VDD