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PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
PM7340 S/UNI-IMA-8
DATA SHEET
PMC-2001723
ISSUE 3
INVERSE MULTIPLEXING OVER ATM
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
19
Pin Name
Type
Pin
No.
Function
RCA
Tristate
Output
AB22
The
Receive Cell Available
(RCA) is an active high
signal that, when polled using the RADR[4:0]
signals, indicates if at least one cell is queued for
transfer on the selected logical channel FIFO .
The S/UNI-IMA-8 device drives RCA with the cell
availability status for the polled port one RCLK cycle
after a valid RADR[4:0] address is sampled. The
RCA output is high-impedance at all other times.
The RCA output is updated on the rising edge of
RCLK.
RENB
Input
W20
The
Receive Enable Bar
(RENB) is an active low
signal used to initiate the transfer of cells from the
S/UNI-IMA-8 to an ATM-layer component, such as a
traffic management device.
The RENB input is sampled on the rising edge of
RCLK.
RADR[4]
RADR[3]
RADR[2]
RADR[1]
RADR[0]
Input
AA22
Y21
V20
Y22
W22
The
Receive Address
(RADR[4:0]) signals are
used to address the S/UNI-IMA-8 device for the
purposes of polling and selecting for cell transfer.
The RADR[4:0] input bus is sampled on the rising
edge of RCLK.
RSOC
Output
V19
The
Receive Start of Cell
(RSOC) is an active high
signal that marks the first word of the cell on the
RDAT[15:0] bus.
The RSOC output is updated on the rising edge of
RCLK.