Thingiverse

Touchpad drawing toy

by akosboda

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0 Makes

Touchpad demo, drawing toy

Touchpad could be a cheap and versatile input device for Arduino (source : old laptop). Add two switches for mouse-like operation to select-unselect any position on the TFT screen.

Parts: Synaptics-like touchpad, Arduino, TFT ST7735 1.8", 5V to 3.3V level shifter 4 units, 10K 20K resistor divider for Reset signal to TFT. STM32 needs no level shift.

This project reads absolute values from Synaptics touchpads, and draws a dot in selectable colors on TFT.

Touchpad typical X Y coordinates range from 950 to 5000, depending on model. This range gets transferred to 128x160 pixels on the TFT for draw. Z coordinate (touch strength) range 0-255. Draws a dot if z>10, light touch. Select draw color on the color bars, clear the image touching the left bottom corner.

Code uses no libraries. Tested on Arduino Nano and STM32 Blue Pill. Connect to T10 clock and T11 data points on touchpad, all touchpads worked right away for me. See Youtube how to find T10 and

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Source

Thingiverse

What you need to print this: Beginner Low confidence

Single piece

Supports 1/3

Assembly 0/3

Settings 1/3

Bed size 0/3

Post-process 0/3

Printer

FDM / FFF

File format