BYPASSING button on teensy 4.0

[aadityaa58]

I am planning to use the teensy 4.0 board for a master-slave configuration where teensy 4.0 will be my master and both will be enclosed in a container while the program runs on the master board the issue is if I want to make some changes in the code and then upload it again the button present on the teensy 4.0 board has to pressed every time code is uploaded so for that I have to again open its waterproof container and press the button so I wanted to know if there is any way where we can bypass this button press thing then it would be really helpful to me.

[defragster]

This means the enclosed waterproof container has an available USB port for programming?

If the Teensy is properly running and has an active USB stack programming doesn't require a button press?

The USB cable connected to program can tell the Teensy to enter the bootloader mode for code upload.

If not running properly or not having USB code embedded to recognize this request it could be done in software carefully (RE)using any existing input buttons, or the Program through hole on the Teensy PCB could be attached to a unique button to put the Teensy into bootloader mode for programming.

[Frank B]

Yes, that sounds like a problem in the program.
Or maybe you have disabled the interrupts?

[WMXZ]

I use 5 lines into my waterproof housing
Voltage, Ground, USB D+, USB D-, Program line
this allows me to reprogram Teensy at all circumstances.