I am not sure if this is the best place to ask my question, but I couldn't find any other. I was reading this Cypress manual: https://www.cypress.com/file/136666/download and in the section about the data codes it is said (page 61):
"In 8DR mode, each symbol represents eight bits of user data. The 32-chip codes are used for 250 Kbps rate and 64-chip codes are used for 125 Kbps rate. In this proprietary mode, 128 derivative PN codes are generated based upon the organization of the contents of the DATA_CODE_ADR file register 0x23"
The question is how to derive 128 different PN codes from a register file, which consists of only 2? The manual doesn't seem to give an answer to that/