I2C Switch - abaco systems RTM311 User Manual

UM082 RTM311 User Manual
7.3.3

I2C switch

The I2C interface connects to I2C Master signals that come from the VPX connector pins:
- LOCAL-I2C_SCL: see section 7.5.1.
- LOCAL-I2C_SDA: see section 7.5.1.
It's called a LOCAL I2C interface, to differ from the SMBus interface on VPX RP0.
The VPX I2C signals connect directly to a I2C level translator PN: TCA9517DGKR, and then to
Texas Instruments part: PCA9548ABS_118. The I2C interface diagram is shown below.
TCA9517
I2C
Side A
MGT and legacy LVDS
QTE 120 pins
M.2 Socket
The slave addresses are shown in Figure 3 and the table below.
Slave
I2C switch
CPLD
DisplayPort driver
SATA Re-driver
Note that: To have access to the I2C interface on DisplayPort driver and SATA re-driver, CPLD's
Command Register 2, bit2 and bit3 must be set, respectively. For more information refer to
Appendix A.
UM082
Muxaddr[2:0], default
Port 1
I2C
Side B PCA9548
P2 P3
I2C
I2C
TCA9517
Side A Side B
Figure 4: Local I2C architecture
www.abaco.com
I2C addr 0x70
I2C
Addr: 0x10
P4
Addr: 0x04
Addr: 0x61
I2C
Slave address (HEX)
0x70
0x10
0x04
0x61
r1.3
CPLD
XC2C256-
7VQG100I
DisplayPort
Driver
SN65DP141
SATA Redriver
DS100BR111
GPIO
Micro
HDMI
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