#10 A good display need an input method

A project log for BW16 Stamp - Tiny 5GHz WiFi Dev Board

Super compact functional 5G Hz WiFi MCU in stamp size with power circuit, work out of the box

SimonXiSimonXi 10/06/2022 at 07:390 Comments

ST7737 TFT SPI LCD display is a vivid and compact display that offer just enough visualization for many microcontrollers and their applications. However, a display without an input method feels void and not interesting, thus I plan to add an input method to the BW16 Stamp!

There are many options out there,

1. Push Buttons

This is the most obvious and easiest ones to add, TTGO dev board has 2 user buttons on the sides of their microcontroller board and are perfect for many applications

TTGO T-Display ESP32 WiFi And Bluetooth Module Development Board 1.14 Inch  LCD Control Board | Shopee SingaporeBut buttons are huge for BW16 Stamp and limited to only max 4 states (with 2 buttons) which might not be enough.

2. 5-way Tactile Switch

5-way tactile switch is just like a joy stick, but it can be slided up, down, right, left and pressed down, so essentially it's a 5-in-1 buttons

5-way Tactile SwitchThis is good when you have many GPIO available, but for BW16 Stamp, our GPIO resources are also limited, so taking up 5 GPIO is a little to much.

3.  Thumbwheel Switch

This switch allows for rotation input, and press-down input which is very common on old-shool MP3/MP4 players

Picture 1 of 12This is almost perfect, as it only need 3 GPIOs, but its size is still too big for our BW16 Stamp...

4. 6-Axis Accelerometer + Gyro sensor

A 6-axis sensor would enable battery-powered device for motion input, which are not limited to the combination of input pattern that other methods have, and they are generally quite small and packed with many interesting features such as "free fall detection", " single tap", "double tap", "rise-hand wakeup" and etc.  What's best? with a motion sensor like this, we can even run TinyML (Tensor Flow Lite for Microcontrollers) on BW16 Stamp!

There are many 6-axis ICs, most popular one I guess is MPU-6050, which is good but a little expensive,

So I got my eye on another model, 


from STMicroelectronics, it's only 1/7 of the price to MPU-6050, and it offers many addition features while still can attain a surprising 3 uA in idle mode!

So this really is a good fit for IoT device and BW16 Stamp!

I will be working on adding this IC into the PCB design and hopefully be able to get some result soon!

Stay tuned and happy making! ~~ :)