The enhanced host port interface (EHPI) on the TMS320VC5509 and TMS320VC5510 DSPs provides a 16-bit port through which a host device may access the internal and external memory space of the DSP. The flexibility of the EHPI interface allows various host devices to interface with the DSP using minimal or no external interface logic. This document describes various possible EHPI configurations and explains how to properly interface the EHPI to a host device. The document also explains the proper sequence for loading boot code to the DSP via EHPI. Summaries of EHPI signal descriptions, register definitions, and EHPI memory maps are included in Appendixes A, B, and C.