PM7385 FREEDM-84A672
DATA SHEET
PMC-1990114
ISSUE 6
84 LINK, 672 CHANNEL FRAME ENGINE AND DATA LINK MANAGER
WITH ANY-PHY PACKET INTERFACE
Pin Name
RENB
Type
Input
Pin
No.
T23
Function
The receive enable signal (RENB) qualifies the
RXADDR[2:0] signals for selection of a
FREEDM-84A672 device. When RENB is
sampled high and then low in consecutive
RXCLK cycles, the address on RXADDR[2:0]
during the cycle when RENB is sampled high
selects a FREEDM-84A672 device enabling it to
output data on the receive APPI. The Rx APPI
of each FREEDM-84A672 device is identified by
the base address in the RAPI672 Control
register.
The polling function of the RXADDR[2:0] and
RPA signals operates regardless of the state of
RENB.
RENB may also be used to throttle the
FREEDM-84A672 during data transfer on the
Rx APPI. When the FREEDM-84A672 samples
RENB high during data transfer, the FREEDM-
84A672 will pause the data transfer and tri-state
the receive APPI outputs (except RPA) until
RENB is returned low. Since the Any-PHY bus
specification does not support deselection
during data transfers, the address on the
RXADDR[2:0] inputs during the cycle before
RENB is returned low must either re-select the
same FREEDM-84A672 device or be a null
address.
To commence data transfer, RENB must be
sampled low following device selection.
It is the responsibility of the external controller to
prevent overflow by providing each FREEDM-
84A672 device on an Any-PHY point to multi-
point bus sufficient bandwidth through selection.
RENB is sampled on the rising edge of RXCLK.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
25
PMC [ PMC-SIERRA, INC ]
