Multiple SPDIF receiver to I2S
Posted: Sat Dec 22, 2018 9:40 am
Hi Guys,
Can someone help me to finalize my HW design by confirming feasibility of the following project ? also a first guidance on the application would be appreciated, just as a confirmation of feasibility and to sense the level of software headach to come :)
I m in the process of designing a multichannel dac board integrating XUF208 and I d like to manage 4 SPDIF receiver, as typically coming out of a player like OPPO-203 with Vanity 203 HD board. In this context the 4 SPDIF signals are synchronized together and generated from a single 44/48k or 88/96 master clock in the player.
The design includes a fractional PLL for generating a proper I2S synch clock, and the xmos will be configured as a single I2S slave channel in TDM8 mode.
the bit clock (11/12/22/24mhz) and the master clock (22/24mhz) are generated from the PLL. The TDM frame clock is generated by a logic divider.
here is a high level diagram of the configuration, and the foreseen 1bit port mapping. I have possibly a spare port (QSP_CLK / P1C0) that coud generate a reference clock for the PLL but I think it is not needed as the ClockGen.xc can calculate the value for the fractional PLL and send them over I2C right ?
Also I understood from other posts that the MCLOCK is not needed for the standard I2S_lib if we do not use XUD/USB right ?
I ve read many xmos application note and source code, including the famous AN00231_ASRC_SPDIF_TO_DAC. this all is inspiring but quite complex.
Many thanks for supporting our creativity!
Can someone help me to finalize my HW design by confirming feasibility of the following project ? also a first guidance on the application would be appreciated, just as a confirmation of feasibility and to sense the level of software headach to come :)
I m in the process of designing a multichannel dac board integrating XUF208 and I d like to manage 4 SPDIF receiver, as typically coming out of a player like OPPO-203 with Vanity 203 HD board. In this context the 4 SPDIF signals are synchronized together and generated from a single 44/48k or 88/96 master clock in the player.
The design includes a fractional PLL for generating a proper I2S synch clock, and the xmos will be configured as a single I2S slave channel in TDM8 mode.
the bit clock (11/12/22/24mhz) and the master clock (22/24mhz) are generated from the PLL. The TDM frame clock is generated by a logic divider.
here is a high level diagram of the configuration, and the foreseen 1bit port mapping. I have possibly a spare port (QSP_CLK / P1C0) that coud generate a reference clock for the PLL but I think it is not needed as the ClockGen.xc can calculate the value for the fractional PLL and send them over I2C right ?
Also I understood from other posts that the MCLOCK is not needed for the standard I2S_lib if we do not use XUD/USB right ?
I ve read many xmos application note and source code, including the famous AN00231_ASRC_SPDIF_TO_DAC. this all is inspiring but quite complex.
Many thanks for supporting our creativity!