Datasheet

DS21Q50
15 of 87
2.1 Pin Function Description
2.1.1 System (Backplane) Interface Pins
Signal Name:
TCLK
Signal Description:
Transmit Clock
Signal Type:
Input
A 2.048MHz primary clock. Used to clock data through the transmit formatter.
Signal Name:
TSER
Signal Description:
Transmit Serial Data
Signal Type:
Input
Transmit NRZ serial data. Sampled on the falling edge of TCLK when IBO disabled. Sampled on the falling edge
of SYSCLK when the IBO function is enabled.
Signal Name:
TSYNC
Signal Description:
Transmit Sync
Signal Type:
Input/Output
As an input, pulse at this pin establishes either frame or multiframe boundaries for the transmitter. As an output,
can be programmed to output either a frame or multiframe pulse.
Signal Name:
RSER
Signal Description:
Receive Serial Data
Signal Type:
Output
Received NRZ serial data. Updated on rising edges of RCLK when the receive elastic store is disabled. Updated on
the rising edges of SYSCLK when the receive elastic store is enabled.
Signal Name:
RSYNC
Signal Description:
Receive Sync
Signal Type:
Input/Output
An extracted pulse, one RCLK wide, is output at this pin, which identifies either frame or CAS/CRC4 multiframe
boundaries. If the receive elastic store is enabled, then this pin can be enabled to be an input at which a frame
boundary pulse synchronous with SYSCLK is applied.
Signal Name:
SYSCLK
Signal Description:
System Clock
Signal Type:
Input
2.048MHz clock that is used to clock data out of the receive elastic store. When the IBO is enabled this can be a
4.096MHz, 8.192MHz, or 16.384MHz clock.
Signal Name:
OUTA
Signal Description:
User Selectable Output A
Signal Type:
Output
A multifunction pin that can be programmed by the host to output various alarms, clocks or data, or used to control
external circuitry.
Signal Name:
OUTB
Signal Description:
User Selectable Output B
Signal Type:
Output
A multifunction pin that can be programmed by the host to output various alarms, clocks, or data, or used to control
external circuitry.