NXP Semiconductors PXN2020 - 5.5.4 SWT Clock Domain; 5.5.5 Input;Output Processor (IOP) Clocking; 5.5.6 FEC Clocking; 5.5.7 Media Local Bus (MLB) DIM Clocking

System Clock Description
PXN20 Microcontroller Reference Manual, Rev. 1
5-14 Freescale Semiconductor
5.5.4 SWT Clock Domain
The clock source for the SWT is the 16 MHz_IRC.
5.5.5 Input/Output Processor (IOP) Clocking
The e200z0 IOP always runs at half the system frequency. If the system frequency source is the
16 MHz_IRC (e.g. after wake-up) the IOP is clocked at 8 MHz.
5.5.6 FEC Clocking
The Fast Ethernet Controller is not capable of running at the target system bus speed of the device. A
permanent divide-by-two prescaler has been introduced into the clock tree for the FEC so that it always
runs at half the speed of the system clock.
5.5.7 Media Local Bus (MLB) DIM Clocking
The MLB DIM always runs at half the system frequency.