2.4.4
IOFPGA clocks
Programmable clock generators on the N1 board generate clocks for the internal systems of the IOFPGA.
The IOFPGA Thin Links interfaces generate clocks for data transmitted to the N1 SoC interfaces. The
IOFPGA also generates the
Serial Configuration Controller
(SCC) clock data strobe.
The following table shows the IOFPGA clocks.
Table 2-3 IOFPGA clocks
Clock
Source
Frequency
Description
IOFPGA_ACLK
OSC9
60MHz
Boot up clock. Drives IOFPGA OSC0.
IOFPGA_TLXCLK
OSC8
80MHz
IOFPGA Thin Links
IOFPGA_PXLCLK
OSC7
23.75MHz
Drives HDLCDPLL. Low
‑
performance pixel
clock output, range 25-100MHz.
IOFPGA_AUDCLK
OSC10
24.576MHz
Drives audio clock
I2SCLK
.
IOFPGA_CLK24M
FPGA_CLK24M
24MHz
Drives MMCM at 100MHz.
IOFPGA
_RSVD
OSC11
24MHz
Reserved
S32KCLK
CLK_32K
32.768kHz
Standalone clock for
Real Time Clock
(RTC)
IOFPGA_DDR3_SYSCLK
GTX clock
100MHz
Drives DDR3 controller reference clock at
400MHz.
Thin Links-based AXI master and
slave interface clocks between
IOFPGA and N1 SoC.
-
75MHz from N1
SoC to IOFPGA.
80MHz from
IOFPGA to N1 SoC.
for
descriptions of Thin Links clocks.
SMBM_CLK
MCC
40MHz
SMB clock
SMBP_CLK
PCC
40MHz
SMB clock
CFG_M2F_CLK
MCC
10MHz
Serial Configuration Controller (SCC)
interface clock. This clock is a data strobe, not
a free running clock.
CFG_CLK
IOFPGA SCC interface 25MHz
Serial Configuration Controller (SCC)
interface clock. This clock is a data strobe, not
a free running clock.
PCIE_CMN_REFCLK
Clock buffer
100MHz
Fixed differential reference clock for PCIe U-
PHY
CCIX_CMN_REFCLK
Clock buffer
100MHz
Fixed differential reference clock for CCIX U-
PHY
2 Hardware description
2.4 Clocks
101489_0000_02_en
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