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Xinyuan-LilyGO / TTGO-T-Display

MIT License
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PIN14 / 80MHZ SPI #42

Open flyandi opened 4 years ago

flyandi commented 4 years ago

So I am looking at the schematics and for some unknown reason the only pin to make 80MHZ IOMUX SPI possible is taken away for voltage measurement.

Is there any particular reason for that or is that something that LilyGo potential could change so we could use 80MHZ SPI .. for radical fast reading / writing speeds on SPI?

image

Thanks,

inoperable commented 4 years ago

You can use pins 25, 26 and 15, for example;

#define CLK_PIN    25
#define MOSI_PIN  26 
#define MISO_PIN  27 
#define CS_PIN      15

CS can be remapped to (almost) any other not used GPIO. Im running the board with 2 * 4 in 1:8x8 Max7219 DotMatrix modules in a chained config, aside from connecting an extra power supply to run the DotMatrix (they put too much load on the ESP32) the board seems to be working fine - although I didn't initialized the built-in OLED.

Gonna update as soon as I put a test a working OLED & MX7219 together

flyandi commented 4 years ago

But those are not IOMUX pins so you are limited to max 40mhz.