[This Figure, callout 11, 12]
The KCU1500 board hosts dual quad (4-channel) small form-factor pluggable (28 Gb/s QSFP+) connectors (J28, J30) that accept 28 Gb/s QSFP+ optical modules. Each connector is housed within a single 28 Gb/s QSFP+ cage assembly. The QSFP0 RX/TX lanes are wired to GTH bank/quad 127, and the QSFP1 RX/TX lanes are wired to GTH bank/quad 128. This Figure shows the 28 Gb/s QSFP+ module connector circuitry typical to each connector.
The QSFP+ connectors J28 and J30 I2C SCL/SDA are accessible through the I2C switch U44 IIC_MAIN_SCL/SDA bus. See I2C Bus.
The QSFP+ connectors J28 and J30 I2C control signals are level-shifted by U39 and U43, respectively, and are connected to FPGA U1 bank 84.
For additional information about the quad small form-factor pluggable (28 Gb/s QSFP+) module, see the SFF-8663 specification for the 28 Gb/s QSFP+ at the SFF-8663 specification website [Ref 13].