[k64f] D5 pin is working abnormally on K64f

[cuiyanx]

Description

As input pin, D5 pin can not recognise low voltage as 'false';

Pin	Input Voltage(V)	Read Value
D5	4.79	true
D5	0	null
D4	4.79	true
D4	0	false

As output pin, output voltage is too high on D5 pin.

Pin	Write Value	Output Voltage(V)
D5	true	3.241
D5	false	2.457
D4	true	3.219
D4	false	1.043

Test Code

/samples/tests/GPIOInputs-k64f.js
/samples/tests/GPIOOutputs-k64f.js

Steps to Reproduction

Run test case and D5 no onchange event.

Actual Result

D5 no onchange event on test case.

Expected Result

Work well as GPIO pin.

Test Builds

Branch	Commit Id	Target Device	Test Date	Result
master	f8f9621	K64f	April 7, 2017	Fail

Additional Information

[grgustaf]

That's a cool bug, very interesting. :)

[grgustaf]

This could turn out to be something we're impacting, with pinmux values in an invalid state and muliple onboard devices driving to the same pin or something like that. But it's also not clear that it's our fault so I'm making it lower priority for now.