SERIAL BACKPLANE TRANSCEIVER
Table 6. S2061 Receiver Pin Assignment and Descriptions (Continued)
S2061
Pin Name
EN_CDET
Level
TTL
I/O
I
Pin #
25
Description
Enable comma detect. When High, enables sync detection.
Detection of the 7-bit comma + character sync pattern, RX(0-9)
= (K28.5:0011111XXX), will enable the word boundary for the
data to follow. When Low, data is treated as unframed data.
(Externally capacitively coupled.) Differential LVPECL received
serial data inputs. RXP is the positive input, and RXN is the
negative input. Internally biased.
Frame Pulse. Active High. When active FP indicates that a
K28.5 character of either disparity has been detected and is
present on RX<0:7>. Note: Byte alignment is performed on the 7
bit comma character with negative disparity (0011111XXX), not
the full K28.5.
Lock Detect. Active High. Indicates that the receiver has
achieved bit synchronization (PLL lock).
K Character Flag. Active High. Indicates the decoded data byte
is a special character (K byte). Control information is indicated
whenever KFLAG is high; a low indicates data.
Byte Error Flag. Active High. Indicates the received byte
contained a character or disparity error.
Signal Detect. Active High when SDPECL is unconnected (logic
0). Active Low when SDPECL is held at logic 1. A single-ended
LVTTL input to be driven by the external optical receiver module
to indicate a loss of received optical power. When SDTTL is
inactive, the data on the RXP/N pins will be internally forced to a
constant zero. When SDTTL is active, data on the RXP/N pins
will be processed normally.
Signal Detect. LVPECL with internal 1 k pull-down. Active High
when SDTTL is held at logic 0. A single-ended 10K LVPECL
input to be driven by the external optical receiver module to
indicate a loss of received optical power. When SDPECL is
inactive, the data on the Serial Data In (RXP/N) pins will be
internally forced to a constant zero. When SDPECL is active,
data on the RXP/N pins will be processed normally. When
SDTTL is to be connected to the optical receiver module instead
of SDPECL, then SDPECL should be tied High to implement an
active low Signal Detect, or left unconnected to implement an
active high Signal Detect.
Receive K Character. Active High. These outputs indicate
reception of the K28.1, K28.3, and K28.7 K characters. (See
Table 4.)
RXP
RXN
FP
Diff.
LVPECL
I
59
61
2
TTL
O
LOCKDET
KFLAG
LVTTL
LVTTL
O
O
64
16
BYTERR
SDTTL
LVTTL
LVTTL
O
I
1
22
SDPECL
LVPECL
I
21
RK0
RK1
LVTTL
O
14
15
February 2, 1999 / Revision C
7
AMCC [ APPLIED MICRO CIRCUITS CORPORATION ]
