TMS320UC5405 datasheet(20/77 Pages) TI

20 / 77 page

Functional Overview

October 2002 − Revised October 2004

SPRS199B

3.1.2 On-Chip ROM With Bootloader

The UC5405 features 4K

× 16-bit of on-chip maskable ROM. Customers can arrange to have the ROM of the

UC5405 programmed with contents unique to any particular application. A security option is available to

protect a custom ROM. This security option is described in the TMS320C54x DSP Reference Set, Volume 1:

CPU and Peripherals (literature number SPRU131). Note that only the ROM security option, and not the

ROM/RAM option, is available on the UC5405 .

A bootloader is available in the standard UC5405 on-chip ROM. This bootloader can be used to automatically

transfer user code from an external source to anywhere in the program memory at power up. If the MP/MC

pin is sampled low during a hardware reset, execution begins at location FF80h of the on-chip ROM. This

location contains a branch instruction to the start of the bootloader program. The standard UC5405 bootloader

provides different ways to download the code to accomodate various system requirements:

•

Serial boot from serial ports 8-bit or 16-bit mode

•

Host-port interface boot

The standard on-chip ROM layout is shown in Table 3−1.

Table 3−1. Standard On-Chip ROM Layout†

ADDRESS RANGE

DESCRIPTION

F000h − F7FFh

Reserved

F800h − FBFFh

Bootloader

FC00h − FCFFh

µ-law expansion table

FD00h − FDFFh

A-law expansion table

FE00h − FEFFh

Sine look-up table

FF00h − FF7Fh

Reserved

FF80h − FFFFh

Interrupt vector table

† In the UC5405 ROM, 128 words are reserved for factory device-testing purposes. Application

code to be implemented in on-chip ROM must reserve these 128 words at addresses

FF00h–FF7Fh in program space.

TMS320UC5405 Datasheet(PDF) 20 Page - Texas Instruments