Do I need this pin? ST7789 DC pin?

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MJU20
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Do I need this pin? ST7789 DC pin?

Post by MJU20 »

I've got a LilyGo T8 V1.1 board with a ESP32-S2 chip and a ST7789 display onboard.

In the properties for the ST7789 display I can not disable the DC pin
st7789-1.jpg
st7789-1.jpg (67.35 KiB) Viewed 179 times
The board doesn't seem to have a DC pin attached to the display.
The display isn't working maybe because of this non existing pin?

Image

Any ideas about this problem?

mnfisher
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Re: Do I need this pin? ST7789 DC pin?

Post by mnfisher »

The display does use a D/C pin (to select data or command)
They have maybe missed it from the diagram?

medelec35
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Re: Do I need this pin? ST7789 DC pin?

Post by medelec35 »

Hello.
I have read that the documentation has errors.
Can you try the following:
CS - 34 (B2)
DC - 37 (B5)
RST - 38 (B6)
LED BL - 33 (B1)
MOSI - 35 (B3)
CLK 36 (B4)
MISO -Any unused pin as not used.


I have not got the hardware to confirm the above connections, So I can't guarantee it will work.
Martin

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Re: Do I need this pin? ST7789 DC pin?

Post by MJU20 »

Thank you both!!

But this doesn't work either..
It seems that the DC pin is not used on the display?

Strange because fresh out of the box it works by showing the LilyGo logo on the screen..
st7789.jpg
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