The documentation of the HID reports for the CP2110/4 is incorrect. In the document known as AN434.pdf, on page 13 it lists the parameters for the Get/Set UART config values, specifying the following values for the Data Bits:
0x05 = 5 data bits
0x06 = 6 data bits
0x07 = 7 data bits
0x08 = 8 data bits
This is incorrect, and I won't admit in public how much time I wasted today beating my head against the desk trying to figure out why I could never set my other UART parameters (principally, the baud rate) because all my attempts were using 0x08 to specify 8 data bits. THIS IS WRONG.
These are the correct values:
0x00 = 5 data bits
0x01 = 6 data bits
0x02 = 7 data bits
0x03 = 8 data bits
Maybe this is obvious to folks familiar with UART config, but I'm a newb, and was trusting the documentation to be the gospel truth. It's not. Please fix it.
I confirm that the data bit values for Get/Set UART Config in the AN434 v0.4 are incorrect, and the values that you have are correct.
Furthermore, I have logged this bug for correction in the next revision of AN434.
For future reference, bugs can be reported by creating a technical support case, where we can confirm the bug. You are also welcome to report bugs here in the forum.