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-------------------------------------------------------------------------------
ST7735 TFT display controller, 4-wire SPI
-------------------------------------------------------------------------------
This capture contains ST7735 TFT display controller communication which is
popular for small (1.44", 1.8") 16-bit color display modules. The protocol
of these modules is based on SPI, but unlike typical SPI has no MISO and uses
two additional pins called RES (reset) and DC (data / command).
Details:
https://cdn-shop.adafruit.com/datasheets/ST7735.pdf
https://github.com/adafruit/Adafruit-ST7735-Library
Logic analyzer setup
--------------------
The 1.44" 128x128 px module was driven by Arduino Uno and Adafruit ST7735
library. The capture was taken with 8 channel noname Saleae logic analyzer
clone, sampling 5 logic channels at a rate of 24MHz:
Probe ST7735
------------------
0 CS (chip select)
1 RES (reset)
2 DC (data / command)
3 MOSI (master out, slave in)
4 SCLK (clock)
Data
----
This is a minimal capture despite the fact that it might look otherwise. It
contains an initialization of a display and filling it with one complete frame.
Long pauses are caused be sleeps for a few hundreds of milliseconds, which are
required by the spec. Other oddities like frequent changes of CS are caused by
specific library implementation.
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