Tool/software:
Hi TI,
We discovered this problem when testing the SPI communication of the TDA4-941-948-MCU link. Using gpio to simulate SPI communication, the speed is relatively slow and unstable.Found in the manual,manual description SPI must in the dual link mode.How to configure 941 to 948 for SPI communication？
Thanks!
Hi Li,
Thank you for asking your question.
The DS90UB941AS and DS90UB948 (or DS90UB940N) can allow SPI communication across the FPD-Link III datapath in dual-link mode.
SPI can be configured to be in Forward Channel mode or Reverse Channel mode.
Forward channel mode is enabled when the SPI controller is local to the Serializer and SPI peripheral is local to the Deserializer. Reverse channel mode is enabled when the SPI controller is local to the Deserializer and SPI peripheral is local to the Serializer. Forward channel mode can pass through SPI at much higher data rates than the Reverse channel.
Something to note is that SPI reads will always take much longer than the writes as the read instruction must be travel in a round-trip back to SPI controller side.
On the DS90UB948 Deserializer side, we can enable the SPI channel mode on main page register 0x43 HSCC_CONTROL[1:0]
Please see sections 7.3.9.2 on Back-channel configuration below:
To support you better, can you elaborate further on your setup:
Thanks,
Ragav Subramanian
