2.9
Chip to Chip communications
Certain connections between master and slave systems are necessary to enable
Cache-Coherent
Interconnect
(CCIX) between two N1 SoCs.
Chip to Chip Sideband signals
Various sideband,
Chip to Chip
(C2C), signals are necessary to enable
Cache-Coherent Interconnect
(CCIX) between two N1 SoCs. The N1 System Development Platform connects these sideband signals
to a 20
‑
pin
Chip to Chip
(C2C) connector on the back panel. A ribbon cable connects the master and
slave N1 System Development Platforms.
C2C interfaces
The sideband interfaces which must be through connected through the C2C connectors are:
•
Cross Trigger Interface
(CTI).
• System counter synchronization.
•
REFCLK
handshaking synchronization.
• SCP I
2
C.
• MCP I
2
C.
• CoreSight debug JTAG.
The following figure shows the CTI and synchronization signals.
N1 board
N1 board
N1 SoC
CNTSYNC_OUT
CNTSYNC_IN
CTSSYNC_OUT
CTSSYNC_IN
CTITRIG_OUT
CTITRIG_IN
CTITRIG_OUTACK
CTITRIG_INACK
N1 SoC
CNTSYNC_OUT
CNTSYNC_IN
CTSSYNC_OUT
CTSSYNC_IN
CTITRIG_OUT
CTITRIG_IN
CTITRIG_OUTACK
CTITRIG_INACK
REFCLK
synchronization
CoreSight
timestamp
synchronization
Cross
Triggers
Master
Slave
Figure 2-10 CTI and synchronization signals
The following figure shows the C2C SCP and MCP I
2
C connections.
2 Hardware description
2.9 Chip to Chip communications
101489_0000_02_en
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