teensy_teen
Active member
Hi, what is the proper way to shut down Teensy 4.1 after use? It is safe to just unplug the usb cable or the battery?
Thank you. How do I know if it needs to complete some EEPROM or SD Card or other data storage for data integrity?
It will be based on the code you write. Unless you have some access or use of those elements - there is nothing in the system that will make use of them.
The Teensy 4.0/4.1 have an additional method, that may be useful depending on what you want to do.
There is a socket on the Teensy 4.0 back row of pins, and the interior row of pins on the Teensy 4.1 just before the micro-SD card. It is next to pin #13 on the Teensy 4.0 and pin #38 on the Teensy 4.1.
If you connect this socket to ground for a given amount of time (default 5 seconds), the Teensy 4.0/4.1 will shut itself off. It will turn itself back on if you release the connection to ground, and then you connect it to ground once again. If you have a battery connected to the RTC (real time clock), it will remember this on/off state even if the Teensy is powered off. If you don't have a battery backed RTC, it will remember the on/off state until the Teensy is powered off.
So, I generally just install a button between that pin and ground, and I hold the button dow until it shuts off. There is a way to change the timeout period.
Thanks @MichaelMeissner. There is a photo of the back of the Teensy 4.1 at:
https://www.pjrc.com/store/teensy41.html (just above USB Host)
I see there is a row of pins next to the winbond memory chip but I cannot find a socket next to pin 38. Which socket are you talking about?