Figure 1-8, Sma connectors (differential), Oscillator top has corner dot marking – Xilinx ML605 User Manual
Page 31: Oscillator body has one square corner

ML605 Hardware User Guide
31
UG534 (v1.8) October 2, 2012
Detailed Description
SMA Connectors (Differential)
A high-precision clock signal can be provided to the FPGA using differential clock signals
through the onboard 50
Ω SMA connectors J58(P)/J55(N). This differential user clock has
the signal names USER_SMA_CLOCK_N and USER_SMA_CLOCK_P.
X-Ref Target - Figure 1-8
Figure 1-8:
ML605 Oscillator Pin 1 Location Identifiers
Oscillator top has
corner dot marking
UG534_08_092109
Oscillator body has
one square corner