Maxim Integrated Secure Microcontroller User Manual

Page 43

Secure Microcontroller User’s Guide

43 of 187

*A 4kB increment (not 2kB) takes place between PA3–0 values 1110b and 1111b.

MCON.3

RA32/8

Range Address

Set the maximum usable address on the bytewide bus.
RA32/8 = 0 sets range address = 1FFFH (8kB)
RA32/8 = 1 sets range address = 7FFFH (32kB)
Set to 1 during a no-V

reset and when the security lock bit is cleared by hardware

or the bootstrap loader. Remains unchanged on all other types of resets.

MCON.2

ECE2

Enable Chip Enable 2

Used to enable or disable the

CE2 signal for the bytewide bus data memory. When

ECE2 = 0, all MOVX instructions activate the

CE1 signal. When ECE2 = 1, all

MOVX instructions activate the

CE2 signal. This bit should always be cleared to 0

in the DS5000, DS5000-32, DS2250-8, and DS2250-32 versions.

MCON.1

PAA

Partition Address Access

Used to protect the programming of the partition address select bits. PA3–0 cannot
be written when PAA = 0. PAA can be written only via the timed-access register.

MCON.0

Security Lock

Indicates that the security lock is set when SL = 1. Can only be modified by the
lock and unlock commands of the bootstrap loader. This bit cannot be modified by
the application software or by the bootstrap loader write command.