The Alveo U55C data center accelerator card provides access to the FPGA through the JTAG interface using the Alveo programmable cable connected to the 30-pin maintenance connector or micro-USB port. Multiplexing control is automatic: when no Alveo programmable cable is plugged into the maintenance connector, all interfaces are connected to micro-USB port. When the Alveo programmable cable is plugged in, all interfaces are re-directed to it.
The maintenance connector pinout supports three UART debug interfaces: PMBus, FPGA JTAG, and satellite controller JTAG. The following figure shows the maintenance connector interface. For more information, see Alveo Programming Cable User Guide (UG1377).