GS3470 datasheet(68/169 Pages) SEMTECH

68 / 169 page

GS3470

Final Data Sheet

Rev.8

PDS-060500

September 2017

68 of 169

Semtech

www.semtech.com

Additionally, the lines from which the packets are to be extracted can be programmed

into the ANC_LINEA and ANC_LINEB registers, allowing ancillary data from a maximum

of two lines per frame to be extracted. If only one line number register is programmed

(with the other set to zero), ancillary data packets are extracted from one line per frame

only. When both registers are set to zero, the device extracts packets from all lines.

To start Ancillary Data Extraction, the ANC_DATA_EXT_MASK bit of the host interface

must be set LOW. Ancillary data packet extraction begins in the following frame (see

Figure 4-36: Ancillary Data Extraction - Step A).

Figure 4-36: Ancillary Data Extraction - Step A

Ancillary data is written into Bank A until full. The Y/1ANC and C/2ANC output flags can

be used to determine the length of the ancillary data extracted and when to begin

reading the extracted data from memory.

While the ANC_DATA_EXT_MASK bit is set LOW, the ANC_DATA_SWITCH bit can be

set HIGH during or after reading the extracted data. New data is then written into Bank

B (up to 1024 x 16-bit words), at the corresponding host interface addresses (see Figure

4-37: Ancillary Data Extraction - Step B).

ANCDATA

1023

ApplicationLayer

ReadPointer

Internal Write

Pointer

BankA

ANC_DATA_SWITCH=LOW

1023

BankB

C00

FFF

GS3470 Datasheet(PDF) 68 Page - Semtech Corporation