N1 board
N1 board
N1 SoC
SCP_I2C0_SDA
SCP_I2C0_SCL
N1 SoC
Master
Slave
SCP_I2C0_SDA
SCP_I2C0_SCL
MCP_I2C0_SDA
MCP_I2C0_SCL
MCP_I2C0_SDA
MCP_I2C0_SCL
Figure 2-11 C2C SCP and MCP I
2
C connections
Chip to Chip powerup synchronization
To enable C2C powerup synchronization, the N1 boards must be connected together with the following
cables:
• 20-pin ribbon cable connecting the C2C connectors on the back panel.
• PCIe adapter cable for the PCIe links, for example, OSS adapter card.
The MCC microSD card must be configured with the master or slave C2C option.
The powerup sequence is:
1. MCC powers up and reads the C2C and master-slave configurations in the microSD card.
2. MCC reads the C2C_PRESENT input pin, on the C2C connector, to determine the power state of the
other system.
3. MCC on the slave side enables the I2C register pullups.
4. MCC updates the SCC registers in the IOFPGA with CHIP_ID and multi-chip support.
5. MCC releases the N1 SoC from reset.
6. The SCP or MCP reads the SCC registers and configures the CCIX root port appropriately:
• CCIX root complex, master.
• CCIX endpoint, slave.
This sequence includes several layers of PCIe and CCIX bring-up across the links to verify the root
complex register configurations, set up the links, and initiate virtual-channel support to enable CCIX
traffic.
C2C connector ribbon cable
The following table shows the C2C ribbon cable wiring and connectivity between the two connected N1
System Development Platforms.
Table 2-9 C2C connector wiring
Master N1 System Development Platform Slave N1 System Development Platform
Pin
Signal
Pin
Signal
1
SCP_SCL
1
SCP_SCL
2
SCP_SDA
2
SCP_SDA
3
GND
3
GND
4
MCP_SCL
4
MCP_SCL
2 Hardware description
2.9 Chip to Chip communications
101489_0000_02_en
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