Eight pads, in order
BL, RST, DC, SCL, MOSI, CS, 3V3, GND, printed down the back of every board in the kit. The backlight is first, the supply is second from last, and the clock is labelled SCL even though this is SPI.
The row, top to bottom
Turn a board over. Down the left-hand edge, in white on black, is a column of eight names. They are the same eight names, in the same order, on every panel in the kit — on the 0.96 inch they run along the top edge instead of down the side, but the order does not change.
Nobody guesses this order. The backlight is the first pad and the supply is second from last, which is the opposite of how almost every other module you will meet is laid out. Read the labels rather than counting from a photograph.
Seven of the eight before anything appears
3V3 and GND are the supply. SCL and MOSI carry the picture. DC and RST and CS decide what the picture means: DC says whether the byte on the wire is a command or a pixel, RST gives the controller a clean start, and CS says this display is the one being addressed.
Get any of those seven wrong and the screen shows you nothing, or shows you white, and the seven failures look identical from across the desk. That is what the fault article is for.
And two names that catch people
The clock pad says SCL. On most boards SCL is an I2C name and SPI clock is SCK, but the silkscreen here uses SCL and there is no other clock pad. It is an SPI clock.
There is no MISO. Nothing comes back out of these panels — you write pixels to them and they hold the picture, and there is no register you can read. A library that asks for a MISO pin wants to be told there is not one.
BL is the pad that is optional and does not feel it
The backlight is a separate circuit from the picture. A panel with BL unconnected is being drawn on perfectly and is simply not being lit, which looks exactly like a panel that is not working at all. Tie it to 3V3 and forget about it, or put it on a spare GPIO and you can dim it — which is less straightforward than it sounds on one of the six.
When it does not work
The clock pad is labelled SCL on these boards. SCL is normally an I2C name and SCK an SPI one, but the silkscreen here uses SCL for both roles and there is no second clock pin to find. Wire it to your board's SPI clock — SCK on an Uno, GPIO 12 on the Lonely Binary ESP32-S3 wiring, GPIO 18 on a classic ESP32.
Correct, and it is not missing. These panels are written to and never read from, so the only data line is MOSI. If a library asks you for a MISO pin, give it -1 or whatever that library uses for none.
You can, and the panel will draw correctly with the lamp off — which looks exactly like a dead display. Tie BL to 3V3 to keep it permanently lit, or to a spare GPIO if you want to dim it. Leaving it floating is the one option that will waste your evening.
Yes. CS has to be held low for the controller to accept anything at all, and nothing on the board holds it there for you. One display still needs a pin, or a wire to ground if you are certain nothing else will ever share the bus.
Two ways onto the same eight pads, and why the ribbon is the one the kit is built around.
The ribbon, or the header →Edit this page — content/books/spi-tft-kit/eight-pads-in-order.mdx
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SPI TFT LCD Display Kit, 6-Pack from 0.96 to 3.5 inch
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