56F8366 datasheet(137/184 Pages) FREESCALE

137 / 184 page

Introduction

56F8366 Technical Data, Rev. 6

Freescale Semiconductor

137

Preliminary

7.2.4

Product Analysis

The recommended method of unsecuring a programmed device for product analysis of field failures is via

the backdoor key access. The customer would need to supply Technical Support with the backdoor key

and the protocol to access the backdoor routine in the Flash. Additionally, the KEYEN bit that allows

backdoor key access must be set.

An alternative method for performing analysis on a secured hybrid controller would be to mass-erase and

reprogram the Flash with the original code, but modify the security bytes.

To insure that a customer does not inadvertently lock himself out of the device during programming, it is

recommended that he program the backdoor access key first, his application code second, and the security

bytes within the FM configuration field last.

Part 8 General Purpose Input/Output (GPIO)

8.1 Introduction

This section is intended to supplement the GPIO information found in the 56F8300 Peripheral User

Manual and contains only chip-specific information. This information supercedes the generic information

in the 56F8300 Peripheral User Manual.

8.2 Memory Maps

The width of the GPIO port defines how many bits are implemented in each of the GPIO registers. Based

on this and the default function of each of the GPIO pins, the reset values of the GPIOx_PUR and

GPIOx_PER registers change from port to port. Tables 4-29 through 4-34 define the actual reset values of

these registers.

8.3 Configuration

There are six GPIO ports defined on the 56F8366/56F8166. The width of each port and the associated

peripheral function is shown in Table 8-1 and Table 8-2. The specific mapping of GPIO port pins is

shown in Table 8-3.

56F8366 Datasheet(PDF) 137 Page - Freescale Semiconductor, Inc