01-09-2025, 11:56 AM
Hi I would like to know about the i2s model and interface used in pulpissimo.Im using the I2s vip with the RTL at RTL github and the reference manual at Doc .I had configured the i2s vip as master (using the i2c)that transmits the data and udma as slave to receive it.
Upon observation ,I noticed that :
The I2s vip transmits data but starts the ws line after the first word.causing the udma i2s to only start receiving data from the second word (the first word is lost).Is this a problem with the i2s vip or due to design considerations involving the i2s protocol.
Some further doubts on :
1)What is the function of snap enable in the i2s vip .
2)How do I enable pdm mode in the i2s receiver udma side.There seems to be working registers for it and configuration wires for it but the documentation is not very clear.
Is it functional and can the i2s interface be configured to accept data in pdm mode?
Does it require only two lines ,the clk and data ?
Also the register documentation seems incomplete with a pdm enable bit that's not in the reference manual with regards to the i2s pdm setup register on page 91 of the manual.
Upon observation ,I noticed that :
The I2s vip transmits data but starts the ws line after the first word.causing the udma i2s to only start receiving data from the second word (the first word is lost).Is this a problem with the i2s vip or due to design considerations involving the i2s protocol.
Some further doubts on :
1)What is the function of snap enable in the i2s vip .
2)How do I enable pdm mode in the i2s receiver udma side.There seems to be working registers for it and configuration wires for it but the documentation is not very clear.
Is it functional and can the i2s interface be configured to accept data in pdm mode?
Does it require only two lines ,the clk and data ?
Also the register documentation seems incomplete with a pdm enable bit that's not in the reference manual with regards to the i2s pdm setup register on page 91 of the manual.