Spi Readback Registers; Spi Data Formats - Slave Mode; Table 69: Configuration Vbi Standard To Be Output On Spi Interface; Table 70: Standard Spi Slave Mode Output Format - Analog Devices ADV7850 Hardware Manual

10.7

SPI READBACK REGISTERS

For all VBI data standards, the user can read back the decoded data on lines through the SPI interface. Users can select the standard(s)
they want to read through the SPI registers. A FIFO is used in the VDP to facilitate storage of decoded data while data is being read
through the SPI interface. The data in FIFO is arranged in the following order:
• Type of standard (VBI_DATA_STD)
• Number of data bytes that follow (packet size)
• Decoded data bytes
After setting the required bits, the user can read back the decoded data from the registers addressed 0xC4 to 0xF0 in the VDP Map. The
first two bytes of the registers let the user know the type of standard for which the data is available and the number of data bytes to be
read.
Table 69 explains the bits to be set for different VBI data that are available through the fast I
vdp_fast_reg_ vdp_fast_reg_
conf_cus , conf_cust,
VDP Map 0xC0[7] VDP Map
0xC0[6]
0 0
0 0
0 0
0 0
0 0
0 0
0 0
0 1
1 0
SPI Data Formats – Slave Mode
10.7.1
The ADV7850 will always be configured in SPI master mode when transferring to the ADV8003. However, the ADV7850 can also output
VBI data over SPI in slave mode. The format of these packets is shown in
Rev. A May 2012

Table 69: Configuration VBI Standard to be Output on SPI Interface

vdp_fast_reg_ vdp_fast_reg_conf
conf_ccap, _gem1x_2x,
VDP Map VDP Map
0xC0[5] 0xC0[4]
0 0
0 0
0 0
0 0
0 0
0 1
1 0
0 0
0 0

Table 70: Standard SPI Slave Mode Output Format

Byte No. Contents
0 0x00
1 XX
2 YY
3 ZZ
4 ZZ
5 ZZ
6 xx
7 xx
xx
xx
xx
0xFD
XX
YY
vdp_fast_reg_ vdp_fast_reg_
conf_cgms_ conf_vitc,
wss, VDP Map
VDP Map 0xC0[2]
0xC0[3]
0 0
0 0
0 0
0 1
1 0
0 0
0 0
0 0
0 0
Table 70 to Table
Description
Dummy byte
Number of bytes in this block
VBI standard and field information
Framing Code
Framing Code
Framing Code
VBI Data N
VBI Data N-1
VBI Data 2
VBI Data 1
More data in FIFO
Number of bytes in this block
VBI standard and field information
Framing Code
322
C registers.
2
vdp_fast_reg_conf_ vdp_fast_
vps_cgmstb, reg_conf_
VDP Map ttxt,
0xC0[1] VDP Map
0xC0[0]
0 0
0 1
1 0
0 0
0 0
0 0
0 0
0 0
0 0
75.
ADV7850
Description
None
(default)
Teletext
VPS
VITC
CGMS/WSS
Gemstar
1x/2x
CCAP
Custom
Mode1
Custom
Mode2