CHAPTER 25 OPTION BYTE
Preliminary User’s Manual U17260EJ3V1UD
556
Figure 25-1. Format of Option Byte (2/2)
Address: 0081H/1081H
Notes 1, 2
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0
POCMODE
POCMODE
POC
mode
selection
0
1.59 V POC mode (default)
1
2.7 V/1.59 V POC mode
Notes 1.
POCMODE can only be written by using a dedicated flash programmer. It cannot be set during self-
programming or boot swap operation during self-programming (at this time, 1.59 V POC mode (default)
is set). However, because the value of 1081H is copied to 0081H during the boot swap operation, it is
recommended to set a value that is the same as that of 0081H to 1081H when the boot swap function
is used.
2.
To change the setting for the POC mode, set the value to 0081H again after batch erasure (chip
erasure) of the flash memory. The setting cannot be changed after the memory of the specified block
is erased.
Caution Be sure to clear bits 7 to 1 to 0.
Address: 0082H/1082H, 0083H/1083H
Note
7 6 5 4 3 2 1 0
0 0 0 0 0 0 0 0
Note
Be sure to set 00H to 0082H and 0083H, as these addresses are reserved areas. Also set 00H to 1082 and
1083H because 0082H and 0083H are switched with 1082H and 1083H when the boot swap operation is
used.
Address: 0084H/1084H
Notes1, 2
7 6 5 4 3 2 1 0
0 0 0 0 0 0
OCDEN1
OCDEN0
OCDEN1
OCDEN0
On-chip debug operation control
0 0
Operation
disabled
0 1
Setting
prohibited
1
0
Operation enabled. Does not erase data of the flash memory in case authentication
of the on-chip debug security ID fails.
1
1
Operation enabled. Erases data of the flash memory in case authentication of the
on-chip debug security ID fails.
Notes 1.
Be sure to set 00H (on-chip debug operation disabled) to 0084H for products not equipped with the on-
chip debug function (
µ
PD78F0531, 78F0532, 78F0533, 78F0534, 78F0535, 78F0536, and 78F0537).
Also set 00H to 1084H because 0084H and 1084H are switched at boot swapping.
2.
To use the on-chip debug function with a product equipped with the on-chip debug function
(
µ
PD78F0537D), set 02H or 03H to 0084H. Set a value that is the same as that of 0084H to 1084H
because 0084H and 1084H are switched at boot swapping.
Remark
For the on-chip debug security ID, see
CHAPTER 27 ON-CHIP DEBUG FUNCTION (
µ
PD78F0537D
ONLY)
.