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