I am running a simple loopback project which came with the DSK-INET daughter card ( with Wiznet w5300 iEthernet Chip) from Bitec using DSK6713 platform from Texas Instruments. In this Project, author Midnight Cow, has followed version 1.1.1 of wiznet w5300 ethernet controller APIs. This project contains 3 source files (main.c, socket.c and w5300.c). In one header file , w5300.h, a constant is defined by #define DSP_SHIFT (1) statement. In the data sheet of w5300, Register Address Offsets are clearly mentioned to access these registers from DSK6713 but in the given code Address Offset of every register is left shifted by DSP_SHIFT value before use and that is also equal to multiply that Offset Address by 2. This makes Adress Offset of a particular register double the value as mentioned in w5300 data sheet.
I do not understand why Midnight Cow (Author of the Code) has done this DSP Shifting of Register Offset Addresses? Please tell me reason behind this?
Thank You All