PSoC1 has two 256 byte pages that support the user module registers. Some of them are located in Bank 0 and some in Bank 1. Whenever a register is mentioned in the text of the device or user module datasheets, there is an indication whether it is in bank 0 or bank 1. Thus, it is required to be in the proper bank for executing an instruction on the register. M8C_SetBank1 macro sets the page to bank 1 and M8C_SetBank0 macro sets the page to bank 0.