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History

Jeff Daly f868d391ec Samples: Fix XEC clock control sample code for MEC172x using new GPIOs. The XEC clock control driver sample code uses enum indexes to offset to the desired GPIO CTRL register of the package. These enums are only used in this example code and are being removed in favor of calculated indexing into the specific GPIO register memory map. Signed-off-by: Jeff Daly <jeffd@silicom-usa.com>		2023-08-23 10:06:13 +02:00
..
boards
src	Samples: Fix XEC clock control sample code for MEC172x using new GPIOs.	2023-08-23 10:06:13 +02:00
CMakeLists.txt
prj.conf
README.rst
sample.yaml	tests: cleanup metadata and filtering	2023-06-13 09:38:27 -04:00

README.rst

.. _clock_control_xec:

Microchip XEC (MEC15xx/MEC172x) clock control driver sample application
#######################################################################

Overview
********

This sample demonstrates configuring the 32KHz clock
options via device tree. The application prints out
hardware configuration and exercises some clock control
driver API's.

Building and Running
********************

The sample can be built and executed on boards using west.
No pins configurations, except GPIO014 is used as indicator for entry/exit and
GPIO060 for 48MHZ PLL clock out.
GPIO221 alternate function 1 is 32KHZ_OUT and can be monitored on Assembly 6915 JP7 pin 5.

Internal Silicon 32KHz Oscillator jumper configuration
MEC172x Assembly 6915

   JP1 pin 2 to GND (ground MEC172x XTAL1 pin)
   JP2 No jumper

Dual-ended 32KHz Crystal jumper configuration
MEC172x Assembly 6915

   Jumper on JP1 1-2 connect crystal Y1 pin 1 to MEC172x XTAL1
   Jumper on JP2 2-3 connect crystal Y1 pin 2 to MEC172x XTAL2

MEC172x Assembly 6906 (baseboard)

   Remove jumper on JP121 to prevent U15 32KHz 50% duty waveform
   from coupling to JP2 on Assembly 6915.

External single-ended 32KHz waveform to MEC172x XTAL2 input
MEC172x Assembly 6915

   JP1 pin 2 to GND (ground MEC172x XTAL1 pin)
   Jumper on JP2 1-2 connect external 32KHz signal to XTAL2

MEC172x Assembly 6906 (baseboard)

   Jumper on JP121 pins 3-4 connect U15 32KHz output to
   XTAL2_32KHZ_IN signal routed to XTAL2 MEC172x pin on Assembly 6915

External single-ended 32KHz waveform to MEC172x 32KHZ_IN pin
MEC172x Assembly 6915

   JP1 pin 2 to GND (ground MEC172x XTAL1 pin)
   Remove jumper on JP2

MEC172x Assembly 6906 (baseboard)

   Jumper on JP121 pins 1-2 connect U15 32KHz output to
   32KHZ_IN pin of MEC172x on Assembly 6915

Sample output
=============

.. code-block:: console

   Prints MEC172x VBAT and PCR register pertaining to power on status and
   clock control.