ws281x: Add WS2801 protocol dump

One universe dump of WS2801 LED strips driving using a AM335x PRU firmware.

Signed-off-by: Matt Ranostay <mranostay@gmail.com>

2 files changed, 46 insertions, 0 deletions

diff --git a/led/ws2801/README b/led/ws2801/README
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+-------------------------------------------------------------------------------
+WS2801 LED strip
+-------------------------------------------------------------------------------
+
+This is a capture of data output an LED universes of 50 RGB LEDS.
+
+Every universe at full capacity of  has a frame size of 768 bytes and can clock
+out at roughly 100 frames per second.
+
+Details:
+ - Koen Kooi's evil vendor tree: https://github.com/koenkooi/kernel
+ - PRU WS2801 firmware: https://github.com/mranostay/ws28xx-lighting-pru
+ - WS2801 datasheet: http://www.adafruit.com/datasheets/WS2801.pdf
+
+
+WS2812B protocol overview
+-------------------------
+
+Each LED receives and the stores the first 24-bits of RGB ordered data then
+passes any more out the Data Output pin to the next LED in the chain.
+
+There is no CS line but latching is done when CLK is held low for >500 uS
+
+This functions as a "reverse" shift register and allows the strip length not to
+be defined in the protocol.
+
+
+Logic analyzer setup
+--------------------
+
+The logic analzyer used was a Saleae Logic16 (at 5mhz)
+
+  Probe       WS2812B LED strip
+  -------------------------
+  1 (black)   Universe #1
+  2 (brown)   Clock
+
+Data
+----
+
+The data contains various RGB values and frames.
+
+The sigrok command line used was:
+
+  sigrok-cli --driver saleae-logic16 --samples 10M --config samplerate=5mhz \
+             -p 0=UNI1,1=CLK -o ws2801_2ch_5mhz.sr
diff --git a/led/ws2801/ws2801_2ch_5mhz.sr b/led/ws2801/ws2801_2ch_5mhz.sr
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index 0000000..40b1d48
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+++ b/led/ws2801/ws2801_2ch_5mhz.sr