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@@ -44,8 +44,15 @@ It's CC-NC. So DIY for yourself and for your friend, don't make money from it.
https://www.lcsc.com/product-detail/Light-Emitting-Diodes-LED_Worldsemi-WS2812B-4020_C965557.html
* TCA9548APWR (TSSOP-24) I2C multiplexer.
https://www.lcsc.com/product-detail/Signal-Switches-Encoders-Decoders-Multiplexers_Texas-Instruments-TCA9548APWR_C130026.html
-* 3x MPR121 modules, there're many types in the market, choose ones like this, and remember to **cut (unshort) the ADDR pin** which is short by default:
- https://www.sparkfun.com/products/retired/9695
+* 3x MPR121 modules, there're many types in the market, choose ones like this, and remember to **cut (unshort) the ADDR pin** which is short by default.
+ https://www.sparkfun.com/products/retired/9695
+ There's not enough space for the whole height of MPR121 module plus the lead pads. So you need to solder the module like the picture shows below.
+ First apply some insulation tape.
+ 
+ Then solder the module directly against the PCB.
+ 
+ You can use the pins comes with the module, but you need to cut away the plastic pads.
+ 
* 5x Sharp GP2Y0E03 ToF sensors, buy ones that equipped with cables.
https://www.lcsc.com/product-detail/Angle-Linear-Position-Sensors_Sharp-Microelectronics-GP2Y0E03_C920270.html
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