Hello,

I am inquiring because there is something wrong with SPI communication using FT4222H.

It works fine at 20Mhz, but if you increase the frequency above, the read data seems to shift by 1 bit.

First, the operation status at 20Mhz.(Sysclk = 80Mhz, DIV = 4)
When I send a command, it responds with 0x2016. Normal operation.
Both the signal waveform and read data are normal.

But it's different at 24Mhz.(Sysclk = 48, DIV = 2)
When I send a command, it responds with 0x100B.
If you look at the signal waveform, it seems to be 0x2016, but in the read data, it reads 0x100B.

I found 0x2016 to be 0x100B if I shift 1 bit right.

I need advice on this phenomenon. Please help me.
Attach the waveform and read data screenshot.