This version (07 Feb 2022 13:23) was approved by Laszlo Nagy.The Previously approved version (15 Apr 2020 15:05) is available.Diff

JESD204B Glossary

Control characters

/R/ K28.0 Initial lane alignment sequence multi-frame start.
/A/ K28.3 Lane alignment
/Q/ K28.4 Initial lane alignment sequence configuration marker.
/K/ K28.5 Code group synchronization.
/F/ K28.7 Frame synchronization.


CGS Code Group Synchronization
ILAS Initial Lane Alignment Sequence
LMFC Local Multi Frame Clock
LEMC Local Extended Multiblock Clock
MCDA Multiple Converter Device Alignment
NMCDA No Multiple Converter Device Alignment
RBD RX Buffer Delay
EMB Extended Multiblock
EoMB End-of-multiblock sequence (00001)
EoEMB End of extended multiblock identifier bit
L Lane Count
M Converter Count
F Octets per Frame per Lane
S Samples per Converter per Frame
NP Total Number of Bits per Sample
N Converter Resolution
K Frames per Multiframe
HD High Density User Data Format
E Number of multiblocks in an extended multiblock


character clock Clock with which 8b10b characters and octets are generated.
conversion clock Clock used by a converter device to perform the A2D or D2A conversion.
link clock Link parallel clock feeding the link layer, lane rate / 40 or lane rate / 80 for 204B links, lane rate / 66 for 204C 64b66b links
device clock Master clock supplied to the JESD204B device from which all other clock signals must be derived. In context of FPGA is an integer multiple of frame clock, used directly in link, transport and application layers.
frame clock Clock rate at which samples are generated/processed. Has the same rate as the conversion clock, except for interpolating DACs or decimating DACs, where it is slower by the interpolation/decimation factor.
line clock Clock for the high-speed serial interface.
local clock A clock generated inside a JESD204B device.
SYSREF clock Slow clock used for cross-device synchronization purposes.

All clocks inside a JESD204B system must have a integer relationship.

resources/fpga/peripherals/jesd204/jesd204_glossary.txt · Last modified: 07 Feb 2022 12:30 by Laszlo Nagy