Analog Devices ADV8005 Hardware Reference Manual page 175

ADV8005 Hardware Reference Manual UG-707
Config
Register
OSD_CORE
SPI SPI I2C
Master Slave Slave
FLASH System
DDR2 Memory
MEM Controller(CPU)
Figure 87: MCU as SPI Master Sending OSD Data Through ADV8005 SPI Slave Interface
Additionally, the system MCU (SPI master) can program the external flash by looping SPI commands through the SPI slave (serial port 1) and
the SPI master (serial port 2) interfaces connected in a chain. In this mode, the OSD core just passes through MOSI, SS and SCLK signals from
the MCU to the flash. Note that the system MCU is responsible for any error protection in this mode, as shown in Figure 88.
This option can be useful during the final debug stage of the OSD, in which the OSD design could be downloaded into the system SPI flash
memory through, for example, the USB or RSR232 port of the MCU.
This mode can be enabled using the spi_loop_through mode which controls the mux shown in Figure 88.
Rev. A | Page 175 of 317