Nonvolatile Registers:
There are two Nonvolatile Registers named
OR0
and
OR1
individually. They are designed to
configure the MPC89x51A options.
Generally these two nonvolatile registers will be written via a popular NVM writer, say Hi-Lo
System All-11, Leaper-48 and Megawin-Provided MCU writer. Furthermore, the user can change
the NVM register
OR1
by the ISP program in a manner as same as writing the
data flash,
but
OR0
can only be written via an off-line popular NVM writer.
NVM register: OR0
(Option
Register 0):
Bits-7
-
Bits-6
-
Bits-5
ISPAS1
Bits-4
ISPAS0
Bits-3
-
Bits-2
MOVCL
Bits-1
SB
Bits-0
LOCK
{ISPAS1,
ISPAS0}:
Used to identify the start address for ISP program
{0,
0}:=
The ISP space is from 0x2C00 to 0x3BFF (4K size).
{0,
1}:=
The ISP space is from 0x3400 to 0x3BFF (2K size).
{1,
0}:=
The ISP space is from 0x3800 to 0x3BFF (1K size)
{1,
1}:=
No ISP space.
These two bits decide where the ISP program locates, and how the ISP program and the
data flash
shares
the 11K embedded flash.
MOVCL:
Used to determine if MOVC instruction will be disabled.
0:=
MOVC is conditionally disabled.
1:=
MOVC is always available.
SB:
Used to determine if the program code will be scrambled while it is dumped.
0:=
Code dump from Writer is scrambled.
1:=
Code dump from Writer is transparent.
LOCK:
Used to determine if the program code will be locked against the popular writer.
0:=
lock code.
1:=
does not lock code
If the code is locked, all the data dumped from a popular will always show
FFh.
Please check file “initial Configuration.pdf” to get the default value of the OR0.
10
MPC89x51A Data Sheet
MEGAWIN
MEGAWIN [ MEGAWIN TECHNOLOGY CO., LTD ]
