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S/UNI-JET Data Sheet
Released
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
39
Pin Name
Type
Pin
No.
Function
TPOHFP
TFPO
TMFPO
TGAPCLK
Output
W14
The Transmit Path Overhead Frame Position (TPOHFP)
is valid when the FRMRONLY bit in the S/UNI-JET
Configuration 1 Register is logic zero. The TPOHFP
output locates the individual PLCP path overhead bits in
the transmit overhead data stream, TPOH. TPOHFP is
logic one while bit 1 (the most significant bit) of the path
user channel octet (F1) is present in the TPOH stream.
TPOHFP is updated on the falling edge of TPOHCLK.
The Framer Transmit Frame Pulse/Multi-frame Pulse
Reference (TFPO/TMFPO) is valid when the S/UNI-JET
is configured as a DS3, E3, or J2 framer for non-ATM
applications by setting the FRMRONLY bit in the S/UNI-
JET Configuration 1 Register to logic one and the
TXGAPEN bit in the S/UNI-JET Configuration Register to
logic zero.
TFPO pulses high for 1 out of every 85 clock cycles
when configured for DS3, giving a free-running mark for
all overhead bits in the frame. TFPO pulses high for 1 out
of every 1536 clock cycles when configured for G.751
E3, giving a free-running reference G.751 indication.
TFPO pulses high for 1 out of every 4296 clock cycles
when configured for G.832 E3, giving a free-running
reference G.832 frame indication. TFPO pulses high for
1 out of every 789 clock cycles when configured for J2,
giving a free-running reference frame indication.
TMFPO pulses high for 1 out of every 4760 clock cycles
when configured for DS3, giving a free-running reference
M-frame indication. TMFPO pulses high for 1 out of
every 3156 clock cycles when configured for J2, giving a
free-running reference multi-frame indication. TMFPO
behaves the same as TFPO for E3 applications.
TFPO and TMFPO are updated on the rising edge of
TICLK or RCLK if loop-timed.
The Framer Gapped Transmit Clock (TGAPCLK) is valid
when the S/UNI-JET is configured as a DS3, E3, or J2
framer for non-ATM applications by setting the
FRMRONLY bit in the S/UNI-JET Configuration 1
Register and the TXGAPEN bit in the S/UNI-JET
Configuration 2 Register.
TGAPCLK is derived from the transmit reference clock
TICLK or from the receive clock if loop-timed. The
overhead bit (gapped) positions are generated internal to
the device. TGAPCLK is held high during the overhead
bit positions. This clock is useful for interfacing to devices
which source payload data only.
TGAPCLK is used to sample TDATI.