Two flags are forwarded to the FPGA fabric:
•
rx_rmfifodatadeleted
- Asserted for two clock cycles for each deleted /I2/ ordered set to indicate
the rate match FIFO deletion event
•
rx_rmfifodatainserted
- Asserted for two clock cycles for each inserted /I2/ ordered set to indicate
the rate match FIFO insertion event
For more information about the rate match FIFO, refer to the
Transceiver Architecture for Cyclone V
chapter.
GbE Protocol-Ordered Sets and Special Code Groups
Table 4-5: GIGE Ordered Sets
The following ordered sets and special code groups are specified in the IEEE 802.3-2008 specification.
Encoding
Number of Code
Groups
Ordered Set
Code
Alternating /C1/ and /C2/
—
Configuration
/C/
/K28.5/D21.5/
Config_Reg
(12)
4
Configuration 1
/C1/
/K28.5/D2.2/
Config_Reg
4
Configuration 2
/C2/
Correcting /I1/, Preserving /I2/
—
IDLE
/I/
/K28.5/D5.6/
2
IDLE 1
/I1/
/K28.5/D16.2/
2
IDLE 2
/I2/
—
—
Encapsulation
-
/K23.7/
1
Carrier_Extend
/R/
/K27.7/
1
Start_of_Packet
/S/
/K29.7/
1
End_of_Packet
/T/
/K30.7/
1
Error_Propagation
/V/
Table 4-6: Synchronization State Machine Parameters in GbE Mode
Setting
Synchronization State Machine Parameters
3
Number of valid {/K28.5/, /Dx,y/} ordered sets received to achieve
synchronization
4
Number of errors received to lose synchronization
4
Number of continuous good code groups received to reduce the error
count by 1
(12)
Two data code groups represent the
Config_Reg
value.
Altera Corporation
Transceiver Protocol Configurations in Cyclone V Devices
4-15
Gigabit Ethernet Transceiver Datapath
CV-53004
2013.10.17