2.4
Clocks
The N1 SDP clocks drive the board and the N1 SoC.
This section contains the following subsections:
•
•
•
2.4.3 Clock programming and control
•
2.4.1
Overview of clocks
Programmable clock generators on the N1 board generate clocks for the board peripherals, internal
blocks in the IOFPGA, and the systems in the N1 SoC.
Phase-locked loops (PLLs) generate internal clocks in the N1 SoC for the processor clusters and other
systems.
During powerup or reset, the MCC programs the clock generators according to default values defined in
the
io_v0.txt
configuration file. You can change the operational clock frequencies by modifying the
io_v?.txt
configuration file.
Note
Arm recommends that you operate the N1 board at the default clock frequencies.
2.4.2
SoC clocks
Programmable clock generators on the N1 board drive PLLs in the N1 SoC which generate the internal
N1 SoC clocks.
The following figure shows the programmable clock generators on the board, OSC0-OSC6, and the
internal clocking scheme of the N1 SoC.
2 Hardware description
2.4 Clocks
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