Various external clock inputs/outputs are needed to drive the device. Summary of these input clock signals is as follows:
- WKUP_OSC0_XO/WKUP_OSC0_XI — external main crystal
interface pins connected to the internal high-frequency
oscillator (WKUP_HFOSC0), which is the default clock source
for internal reference clock HFOSC0_CLKOUT.
- LFOSC0_XO/LFOSC0_XI — external crystal interface pins
connected to internal low-frequency oscillator (LFOSC0),
which sources optional 32768Hz reference clock.
- General purpose clock inputs
- WKUP_EXT_REFCLK0 — optional external system
clock.
- EXT_REFCLK1 — optional external system
clock.
- External CPTS reference clock input
- CP_GEMAC_CPTS0_RFT_CLK — optional reference clock
input for CPTS_RFT_CLK.
- External audio reference clock
inputs/outputs
- AUDIO_EXT_REFCLK[1:0] — optional McASP
high-frequency input clocks when configured to
operate as an input.
For more information about Input clock interfaces, see Clocking section in Device Configuration chapter in the device TRM.