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LilyGO / TTGO-T4-DEMO

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SPI & avaialble PINS #10

Open minkione opened 4 years ago

minkione commented 4 years ago

Which pins are still free from the TFT in order to be connected to another SPI device? (example like cc1101)

spleenware commented 4 years ago

Damn, I have exactly the same question. Have you found any answers? @minkione

lockie555 commented 11 months ago

From my explorations it would seem that it cannot be done if you want to use both the sd card and the TFT screen of the TTGO T4. The designers did not bring any of the SPI pins out to the jumper except for pin 19. What a pity as such a device would have been very useful with SPI peripherals as well as I2C. Of course, if you do not need the SD card you can take over the VSPI bus with software defined pins using the jumper and GPIO pins provided. I am into datalogging so I need the SD card and it seems a pity to use an I2C oled screen when such a good TFT screen is already built in. Let us hope that future designs take this need for SPI into account.