Ebay-purchased device. About $20 with free shipping from Hong Kong. There appear to be a few variants. Dimensional drawing below is the two-header version, while there's also a variant with header only on the bottom side of the LCD and an SD card holder.


1 5V 5V power supply When powered from 5V supply,
Pin 1 & Pin 2 as power input,
Pin 33 & Pin 34 provide 3.3V output.
2 GND Ground GND
3 D0 Data lines D0-D15
4 D1
5 D2
6 D3
7 D4
8 D5
9 D6
10 D7
11 D8
12 D9
13 D10
14 D11
15 D12
16 D13
17 D14
18 D15
19 CS LCD chip select Low active
20 RS Instruction/Data register selection RS = 1 : Instruction Register
RS = 0 : Data Register
21 WR Write WR = 0, RD = 1
22 RD Read WR = 1, RD = 0
23 RESET Reset the controller chip Low active
24 NC Not connect Not connect
25 BLVCC 5V or 3.3V Backlight VCC
26 BLGND Ground Backlight GND
27 BLCNT Backlight brightness adjustment Control the backlight brightness via PWM
28 TP_IRQ Touch screen interrupt Low level while the touch screen detects pressing
29 TP_CS Touch screen chip select Low active
30 TP_SCK Touch screen SPI clock connects to SPI SCK
31 TP_SI Touch screen data input connects to SPI MOSI
32 TP_SO Touch screen data output connects to SPI MISO
33 3.3V 3.3V power supply When powered from 3.3V supply,
Pin 33 & Pin 34 as power input,
Pin 1 & Pin 2 keep NC.
34 GND Ground GND

Remaining pins are NC on the 2-header variant, while the SD variant uses the following additional assignments (unproven -- I probed continuity and cross-checked with published SD pinouts).

Pin No.SymbolDescriptionFunction
35SD_DOSD card data outSPI output
36SD_CLKSD card data clockSPI clock
37SD_DISD card data inSPI input
38SD_/CSSD card chip selectActive low chip select