MC68HC05L28 Datasheet, PDF (21/156 Pages) Motorola, Inc – Flexible general-purpose microcomputer

1
1.2
Mask options on the MC68HC05L28
There is only one mask option on the MC68HC05L28. This is to enable or disable the STOP
instruction. It is programmed during manufacture and must be specified on the order form.
1.2.1 Option register (OPT)
In addition to its mask option, the MC68HC05L28 also has two functions that are programmable
via an options register (OPT). This register can be written to once after a reset, but it can be read
at any time.
Option register (OPT)
Address bit 7
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
State
on reset
$001D
IRQED COPON ???? ?100
IRQED — IRQ edge sensitivity
This bit selects the IRQ0 sensitivity.
1 (set) – The IRQ0 is edge-sensitive.
0 (clear) – The IRQ0 is edge-and-level-sensitive.
Reset clears this bit.
COPON — COP function enable/disable
1 (set) – This bit enables the COP watchdog.
0 (clear) – This bit disables the operation of the COP.
Reset clears this bit.
MC68HC05L28
INTRODUCTION
TPG
MOTOROLA
1-3