CYP15G0401DXA Datasheet, PDF (17/48 Pages) Cypress Semiconductor – Quad HOTLink II Transceiver

PRELIMINARY
CYP15G0401DXA
and dynamic control signals. The transmit modes are listed in
Table 3.
Table 3. Transmit Operating Modes
TX Mode Operating Mode
Word Sync
Sequence SCSEL
Support
Control
TXCTx Function
0 LL None
None
Encoder Bypass
1 LM None
None
Reserved for test
2 LH None
None
Reserved for test
3 ML Atomic
Special
Encoder Control
Character
4 MM Atomic
Word Sync Encoder Control
5 MH Atomic
None
Encoder Control
6 HL Interruptible Special
Encoder Control
Character
7 HM Interruptible Word Sync Encoder Control
8 HH Interruptible None
Encoder Control
The encoded modes (TX Modes 3 through 8) support multiple
encoding tables. These encoding tables vary by the specific
combinations of SCSEL, TXCTx[1], and TXCTx[0] that are
used to control the generation of data and control characters.
These multiple encoding forms allow maximum flexibility in in-
terfacing to legacy applications, while also supporting numer-
ous extensions in capabilities.
TX Mode 0—Encoder Bypass
When the Encoder is bypassed, the character captured in the
TXDx[7:0] and TXCTx[1:0] inputs is passed directly to the
transmit shifter without modification. If parity checking is en-
abled (PARCTL ≠ LOW) and a parity error is detected, the 10-
bit character is replaced with the 1001111000 pattern (+C0.7
character) regardless of the running disparity of the previous
character.
With the encoder bypassed, the TXCTx[1:0] inputs are consid-
ered part of the data character and do not perform a control
function that would otherwise modify the interpretation of the
TXDx[7:0] bits. The bit usage and mapping of these control bits
when the Encoder is bypassed is shown in Table 4.
In this mode the SCSEL input is not interpreted. All clocking
modes interpret the data the same, with no internal linking
between channels.
TX Modes 1 and 2—Factory Test Modes
These modes enable specific factory test configurations. They
are not considered normal operating modes of the device. En-
try or configuration into these test modes will not damage the
device.
TX Mode 3—Atomic Word Sync and SCSEL Control of Special
Codes
When configured in TX Mode 3, the SCSEL input is captured
along with the associated TXCTx[1:0] data control inputs.
Note:
6. LSB is shifted out first.
Table 4. Encoder Bypass Mode (TXMODE[1:0] = LL)
Signal Name
TXDx[0] (LSB)
TXDx[1]
TXDx[2]
TXDx[3]
TXDx[4]
TXDx[5]
TXDx[6]
TXDx[7]
TXCTx[0]
TXCTx[1] (MSB)
Bus Weight
2⁰
2¹
2²
2³
2⁴
2⁵
2⁶
2⁷
2⁸
2⁹
10B Name
a^[6]
b
c
d
e
i
f
g
h
j
These bits combine to control the interpretation of the
TXDx[7:0] bits and the characters generated by them. These
bits are interpreted as listed in Table 5.
Table 5. TX Modes 3 and 6 Encoding
Characters Generated
X X 0 Encoded data character
0 0 1 K28.5 fill character
1 0 1 Special character code
X 1 1 16-character Word Sync Sequence
When TXCKSEL = M, all transmit channels capture data into
their input registers using independent TXCLKx clocks. The
SCSEL input is sampled only by TXCLKA↑. When the charac-
ter (accepted in the Channel-A Input Register) has passed
through the Phase-Align Buffer and any selected parity valida-
tion, the level captured on SCSEL is passed to the Encoder of
the remaining channels during this same cycle.
To avoid the possible ambiguities that may arise due to the
uncontrolled arrival of SCSEL relative to the characters in the
alternate channels, SCSEL is often used as a static configura-
tion input.
Word Sync Sequence
When TXCTx[1:0] = 11, a 16-character sequence of K28.5
characters, known as a Word Sync Sequence, is generated on
the associated channel. This sequence of K28.5 characters
may start with either a positive or negative disparity K28.5 (as
determined by the current running disparity and the 8B/10B
coding rules). The disparity of the second and third K28.5
characters in this sequence are reversed from what normal
8B/10B coding rules would generate. The remaining K28.5
characters in the sequence follow all 8B/10B coding rules. The
disparity of the generated K28.5 characters in this sequence
would follow a pattern of either ++––+–+–+–+–+–+– or
– – ++ – + – + – + – + – + – +.
When TXMODE[1] = M (open, TX modes 3, 4, and 5), the
generation of this character sequence is an atomic (non-inter-
Document #: 38-02002 Rev. *B
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