topic Re: MK64 default output at reset in Kinetis Microcontrollers

MK64 default output at reset

roymessinger — Tue, 24 Jan 2017 12:41:38 GMT

What is the default state of the outputs of the cobtroller immidiately after reset?

Do i need to put pull up/pull down on board?Regarding inputs, do i need to place pull up/pull down on inputs (or outputs) not used?

I've looked in the data sheet but probabely missed it.

Any help will do.

Thanks

Re: MK64 default output at reset

egoodii — Tue, 24 Jan 2017 17:41:31 GMT

The 'reset state' of all control registers is called out in the Reference Manual, including the 'pin mux' table, but the general statement is: 'reset state is the safest possible for any possible interconnect'. That is, analog-in-capable pins will default to said analog-in mode, and digital pins will default to input, most with 'no pull'.

So yes, by-and-large anything you need to have as a 'known state' during/just-after reset will need your own external pull-resistors.

Re: MK64 default output at reset

Robin_Shen — Wed, 25 Jan 2017 00:28:00 GMT

Hi Roy,

Some special function pins need take care. For exmaple: Reset_b\ NMI_b\ VREF_OUT\ JTAG_TMS

I recommend you read the "Chapter 2 General System Setup (Hardware Considerations)" of KQRUG.

Best Regards,

Robin