Hi,
First, I don't know the output-Voltage of a PS/2 keyboard if it is powered with 5V.
But, If it is 5V - you might want to upate this page: https://www.pjrc.com/teensy/td_libs_PS2Keyboard.html for not 5 Volt tolerant Teensys
First, I don't know the output-Voltage of a PS/2 keyboard if it is powered with 5V.
But, If it is 5V - you might want to upate this page: https://www.pjrc.com/teensy/td_libs_PS2Keyboard.html for not 5 Volt tolerant Teensys