CY7C924ADX-AI Cypress Semiconductor Corp, CY7C924ADX-AI Datasheet - Page 15

• Manufacturer Part Number: CY7C924ADX-AI
• Manufacturer: Cypress Semiconductor Corp

Specifications of CY7C924ADX-AI

• Number Of Transceivers: 1
• Data Rate: 622Mbps
• Operating Supply Voltage (typ): 5V
• Supply Current (max): 250mA
• Screening Level: Industrial
• Pin Count: 100
• Mounting: Surface Mount
• Package Type: TQFP
• Operating Supply Voltage (min): 4.5V
• Operating Supply Voltage (max): 5.5V
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Lead Free Status / RoHS Status: Not Compliant

Document #: 38-02008 Rev. *E
The read port of the Transmit FIFO is connected to a logic
block that performs data formatting and validation. All data
read operations from the Transmit FIFO are controlled by a
Transmit Control State Machine that operates synchronous to
REFCLK.
Transmit Formatter and Validation
The Transmit Formatter and validation logic perform two
primary functions:
In addition to these logic functions, this block also controls the
timing for the transfer of data from the Transmit Input Register,
Transmit FIFO, or Elasticity Buffer.
Transmit Data Formatting
The CY7C924ADX supports a number of protocol enhance-
ments over a raw physical layer device. These enhancements
are possible in part through the use of the Transmit and
Receive FIFOs. These FIFOs allow the CY7C924ADX to
manage the data stream to a much greater extent than was
possible before. In addition to the standard 8B/10B encoding
used to improve serial data transmission, the CY7C924ADX
also supports:
All three of these capabilities are supported for both 8 and 10
bit encoded character sizes, and are made possible by using
the TXSOC bit. This bit is interpreted, along with TXSC/D* and
TXSVS, in modes where both the Transmit FIFO and the
Encoder are enabled. All three bits determine how the data
associated with them is processed for transmission. These
operations are listed in
The entries in
same characters in the serial data stream as a standard
CY7B923 HOTLink Transmitter. The data, command, and
exception character encodings are listed in the Data and
Special Character code tables
Table 12 on page
Table 2. Transmit Data Formatting
0
0
0
0
1
1
1
1
• Data format control
• Byte-packing
• Marking of packet or cell boundaries using TXSOC
• An expanded command set
• Ability to address and route packets or frames to specific
receivers
0
0
1
1
0
0
1
1
0 Normal Data Encode
1 Replace Character with C0.7 Exception
0 Normal Command Encode
1 Replace Character with C0.7 Exception
0 Send Start of Cell Marker (C8.0) + Data Character
1 Replace Character with C0.7 Exception
0 Send Extended Command Marker (C9.0) + Data
1 Send Serial Address Marker (C10.0) + Data
Character
Character
Table 2
55) found near the end of this data sheet.
Table
where TXSOC is LOW generate the
Data Format Operation
2.
(Table 11 on page 51
and
The 001b, 011b, and 101b character formats instruct the
encoder to discard the associated data character and to
replace it with a C0.7 Exception character.
Excepting the previous 101b case, when the TXSOC bit read
from the Transmit FIFO is HIGH, an extra character is inserted
into the data stream. This extra character is always a Special
Character code (see
remote receiver that the immediately following character
should be interpreted differently from its normal meaning. The
associated character present on TXDATA[x:0] is always
encoded as a data character.
The 100b combination (TXSOC = 1, TXSC/D* = 0, and
TXSVS = 0) is used as a marker for the start of a cell, frame,
or packet of data being sent across the interface. When a
character is read from the Transmit FIFO with this combination
of bits set, a C8.0 Special Character code is sent to the
encoder before sending the associated data character.
The 110b character format expands the command space
beyond that available with the default 8B/10B code. The
8B/10B code normally supports a data space of 256 data
characters, and a command (non-data) space of twelve
command characters (C0.0–C11.0 in
where this is not sufficient, the 110b format can be used to
mark the associated data as an extended command. This
expands the command space to 256 commands (in addition to
some of the present twelve). When a character is read from
the Transmit FIFO with these bits set, a C9.0 Special
Character code is sent to the encoder before sending the data
character.
The 111b character format sends serial addresses to attached
receivers. These serial addresses allow a host to direct (the
following) data to a specific destination or destinations, when
the CY7C924ADX devices are connected in a ring or bus
topology.
The Serial Address marker may also be used to send packet
identification fields, sequence numbers, or other high level
routing information for those point-to-point connections that do
not require physical address capabilities. However, the
reporting of the address field contents may be affected by the
present receiver discard policy. This marking or tagging can be
performed with the 100b or 110b character formats without
concern for receiver discard policy.
When a character is read from the Transmit FIFO with these
bits set, a C10.0 Special Character is sent to the encoder
before sending the associated data character.
Byte Packer
The byte packer is a logical construct that controls the efficient
segmentation of 10 bit source data into 8 bit characters. This
conversion allows these characters to be transported using
8B/10B encoding, with the same encoding overhead (20%) as
when sending 8 bit characters. Because the serializer
continues to operate using 10 bit transmission characters, this
encoding mode only operates with the Transmit FIFO enabled.
The byte packer takes pieces of one or more 10 bit characters,
combines them into 8-bit groups, and passes these groups to
the 8B/10B encoder. It takes exactly five 8 bit characters to
transport four 10 bit characters. The allocation is performed,
as shown in
bits of the first 10 bit character (A[7:0]) are passed to the
Figure 4 on page
Table 12 on page
16, where the low order eight
CY7C924ADX
Table
55) that informs the
12). For data links
Page 15 of 58
[+] Feedback