USB Button Solution

[ajy00]

Hi
If you have no lights that tends to imply a faulty connection… and very unlikely to be a software problem so it’s just a process of elimination!
Can you try another USB socket and/or another PC just to see if you get any connectivity and light..
Then I guess it will be checking the USB cable itself with a multimeter to make sure you have connections to all four wires, and the connection plug has no breaks/loose bits.
Also check the socket on the board … make sure it’s not loose/broken
Beyond that you are into detail circuit checking…
If all else fails you may be spending another $10 for a replacement encoder:(

Good Luck

[wihome]

I was never able to get this working properly- but instead I used Antimicro to run the button mapping for me.

[aakashraj raj]

Hi,
If the USB is connected, the Q1 will conduct and the output will ALWAYS be 0.

If the button is not pressed, R3 will charge the capacitor (in about 7ms to Vbase-on) and the Q2 will turn on, again pulling the output low. JMeter Training in Pune

If the button is pushed, the capacitor will be discharged and the Q2 be turned off, if then Q1 is also off (no USB connected) R2 will pull the output weakly high to the supply voltage. That signal is “strong enough” for a microcontroller, but if you need it to be stronger, you can reduce the resistance or build a sort of H-driver with one PNP and one NPN transistor.

The resistors are chosen such that at 5V the system will not drain more than 0.2mA (both USB connected and SW1 pushed in), reducing the resistances will increase the current draw, increasing them will reduce the consumption.

Be aware that changing R3 will also change the time constant for the switch debounce. Higher value -> stronger debounce / slower release response, lower value -> weaker debounce / higher release response. But you can easily vary the capacitor between 0.1uF and 10uF without any danger, larger values will give slower debounce, smaller will give faster response.

[Anshul]

Can anyone recommend a remote controller to monitor the different functions of the sandbox for use in presentations such as earthquakes, wind, floods and drought?

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