Where to find I2C register information for MAX21000+?
Contact Maxim. We are currently using the chip in a design at my consulting company, and Maxim provided us with a few PDFs that aren't available online. The document you are looking for is named MAX2100x_UG.pdf - it's a 69 page document that goes over the bitfields for every register, as well as some other stuff related to making the chip actually do things. They also gave me some C code examples and a info related to some sort of dev board.