mpc82l54 Megawin Technology, mpc82l54 Datasheet - Page 17

• Manufacturer Part Number: mpc82l54
• Description: 8-bit Micro-controller
• Manufacturer: Megawin Technology

MEGAWIN
NVM register: OR1 (Option Register 1):
NVM register: OR2 (Option Register 2):
{ISPAS1, ISPAS0}:= ISP-Address-Start
HWBS: = Hardware-Boot-Selector
reserved1:= The bit is reserved for afterward user, and should be left at set.
SB: = Used to decide if the program code will be Scrambled while it is dumped.
LOCK: = Used to decide if the program code will be Locked against the popular writer.
OR1 [7:1]:= Used to set the boundary of IAP memory
reserved1:= The bit is reserved for afterward user, and should be left at set.
reserved1
In fact, the boot entrance is determined by register SWBS from SFR ISPCR ignoring the boot
comes from RST-pin press, software-trigger, or power-up. However, if a boot happens and that
boot comes from power-up action, the device will first load the complement of the HWBS to SWBS,
and decides the boot entrance according to the state of bit SWBS. So the HWBS is named
Hardware Boot Selector. It influence on power-up boot, but does not influence on the boot from
RST-pin or software-trigger.
The user must not clear the bit; otherwise, there could be inadvertent effect impacted on the
device.
The user’s application program can change only the IAP flash memory, not of AP flash memory
itself nor the ISP flash memory. The IAP memory is defined between address scope
OR1 [7:1]*512 and ISP-Address-Start. Setting the OR1 [7:1] 1111111
Bit-7
Bit-7
0:= (default)
1:=
0:=
1:= (default)
0:=
1:= (default)
Clearing the bit is to configure the device to boot from ISP program after power-up.
Setting the bit is to configure the device to boot normally from user’s application program
after power-up.
Code dump from Writer is scrambled.
Code dump from Writer is transparent.
Code dumping from Writer is locked.
Permit code dumping from general Writers.
{0,0}:=
{0,1}:=
{1,0}:=
{1,1}:= (default)
OSCDN
Bit-6
Bit-6
Set the ISP start address 3000
Set the ISP start address 3400
Set the ISP start address 3800
Express no ISP code.
HWBS2
Bit-5
Bit-5
MPC82x54A Data Sheet
reserved1
Bit-4
Bit-4
H
H
H
. (ISP code could take 3.5K bytes)
. (ISP code could take 2.5K bytes)
. (ISP code could take 1.5K bytes)
Bit-3
Bit-3
-
reserved1
Bit-2
Bit-2
B
means no IAP memory.
ENROSC
Bit-1
Bit-1
reserved1
Bit-0
Bit-0
-
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