Altera Serial Digital Interface (SDI) MegaCore Function - Manual (Page 40)

3–10 Chapter 3: Functional Description
Block Description
Serial Digital Interface (SDI) MegaCore Function February 2013 Altera Corporation
User Guide
The format block latches the user input en_sync_switch signal for three lines to
realign to a new TRS alignment immediately. During switching, you see zero
interrupt at downstream. The trs_locked and frame_locked signals never get
deasserted during sync switch.
HD-SDI LN Extraction
The HD-SDI LN extraction module extracts and formats the LN words defined by
SMPTE292M section 5.4 from the HD-SDI chroma channel. The design provides the
LN as an output.
HD-SDI CRC Checking
The CRC module checks the CRC defined by SMPTE292M section 5.5 for the HD-SDI
luma and chroma channels.
1 This module is common to the receiver and the transmitter.
The check is implemented by recalculating the CRCs for each received video line and
then checking the results against the CRC data received. If the results differ, an error
flag is asserted. There are separate error flags for the luma and chroma channels. The
flag is held asserted until the next check is performed.
Accessing Transceiver
The Quartus II software enables you to access the transceiver through the
unencrypted ALTGX wrapper file. You can access the ALTGX wrapper files for
Arria II GX, Arria V, Cyclone IV GX, Stratix II GX, and Stratix IV GX configurations.
You can use one of the two following ways to access the ALTGX wrapper files:
■ Edit the ALTGX wrapper file, using legal range provided in the respective device
handbooks.
■ Use analog control through the ALTGX_RECONFIG megafunction.
c Do not reinstantiate the customized ALTGX wrapper file using the MegaWizard
Plug-In Manager so that you do not lose the default content of the wrapper file after
regeneration.
Figure 3–6. Format Block Behavior
en_sync_switch
(previous TRS timing) (new TRS timing)
10
2200 2199 2200
11 12 13
en_sync_switch_reg
line
eav_detect
eav_position
trs_locked/rx_status[3]
frame_locked/rx_status[4]