DS92UT16TUF Datasheet, PDF (33/86 Pages) National Semiconductor (TI) – UTOPIA-LVDS Bridge for 1.6 Gbps Bi-directional Data Transfers

16.0 Embedded Communication
Channel Operation (Continued)
Device 2 transmitter is connected to Device 1 receiver Port
A. This is accomplished by clearing the RAESS bit of the
RACTL register.
ECC Receive on Port B: Device 1 communicating with
Device 3 only.
Device 1: For the ECC to communicate across Link B only,
the ECCA bit of the LKSC register is clear and the ECCB bit
is set. The incoming valid ESS signal received over Link B,
“RxB valid ESS”, is the only one used by the ECC transmit
section in Tx. The RxB port is programmed to extract the
incoming ESSB bit as the valid ESS, as the Device 1 trans-
mitter is connected to Device 3 receiver Port B. This is
accomplished by setting the RBESS bit of the RBCTL regis-
ter.
In this case, when an ECC message is transmitted, the “RxB
valid ESS” signals when the message has been successfully
received by the far-end Device 3. So, ECC communications
only occur over Link B between Device 1 and Device 3.
Device 3: The ECCA bit of the LKSC register is clear and the
ECCB bit is set. The incoming valid ESS signal received
over Link B, “RxB valid ESS”, is the only one used by the
ECC transmit section in Tx. The RxB port is programmed to
extract the incoming ESSB bit as the valid ESS, as the
Device 3 transmitter is connected to Device 1 receiver Port
B. This is accomplished by setting the RBESS bit of the
RBCTL register.
ECC Receive on Port A and Port B: Device 1 communi-
cating with Device 2 and Device 3.
See Figure 18.
Device 1: For the ECC to communicate across both Link A
and Link B, the ECCB and ECCA bits of the LKSC register
are both set. The incoming valid ESS signals received over
Link A “RxA valid ESS” and Link B “RxB valid ESS” are both
used by the ECC transmit section in Tx.
In this case, when an ECC message is transmitted, both the
“RxA valid ESS” and “RxB valid ESS” signals must be used
to indicate that the message has been successfully received
by both Device 2 and Device 3 before a new message can
be transmitted. So ECC communications occur over both
Link A and Link B.
Device 2 and 3: are configured as above for communicating
with only Device 1.
Note that, when Device 1 wants to transmit a new message
it must wait until both Device 2 and Device 3 indicate that
they have received the last message. When Device 2 wants
to transmit a new message it must only wait until Device 1
indicates that it has received the last message. Similarly for
Device 3 transmitting a new message it must only wait until
Device 1 indicates that it has received the last message
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