• 1PPS input or output and ToD input or output—This shielded RJ-45 interface is used for input or output
of time-of-day (ToD) and 1PPS pulses. ToD format includes both NTP and IEEE 1588-2008 time formats.
The same RS422 pins for 1PPS and TOD are shared between input and output directions. The direction for
each can be independently configurable through software.
Use an SMB connector on the front panel for the following:
• GPS 10 Mhz input and output—10 MHz input for GPS Synchronization.
• GPS 1 PPS input and output—1 PPS input for GPS Synchronization.
External Alarm Inputs
The router supports four dry contact alarm inputs through an RJ-45 jack on the front panel.
• Normally Open—indicates that no current flows through the alarm circuit and the alarm is generated
when the current is flowing.
Each alarm input can be provisioned as critical, major, or minor.
Console
The RS232 console port provides transmission (Tx), reception (Rx), and ground (Gnd).
Auxiliary Console
The Auxiliary Console port provides transmission (Tx), reception (Rx), and ground (Gnd).
USB Console
A single USB 2.0 Type-A receptacle on the front panel of the router provides console access to ROMMON,
Cisco IOS-XR and diagnostics. While it uses the Type-A connector, it operates as a USB peripheral only for
connection to an external host computer. This interface requires the use of a Type-A to Type-A connector
instead of a standard USB cable.
Use of the USB console is mutually exclusive of the RS232 console port. This interface requires the use of a
Type-A to Type-A USB cable.
Note
USB Memory
A single USB 2.0 Type-A receptacle on the front panel of the router allows external USB mass storage devices,
such as standard USB flash drives. This interface is used to load images, load or store configurations, write
logs, and so on.
Cisco ASR-920-20SZ-M Aggregation Services Router Hardware Installation Guide
12
Overview
External Alarm Inputs
