UPD78F1502AGK-GAK-AX Datasheet, PDF (848/1031 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcontrollers

78K0R/Lx3
CHAPTER 26 OPTION BYTE
Cautions 1. Be sure to set bits 7 to 3 to “1”.
2. Even when the LVI default start function is used, if it is set to LVI operation prohibition by the
software, it operates as follows:
• Does not perform low-voltage detection during LVION = 0.
• If a reset is generated while LVION = 0, LVION will be re-set to 1 when the CPU starts after reset
release. There is a period when low-voltage detection cannot be performed normally, however,
when a reset occurs due to WDT and illegal instruction execution.
This is due to the fact that while the pulse width detected by LVI must be 200 μs max., LVION =
1 is set upon reset occurrence, and the CPU starts operating without waiting for the LVI
stabilization time.
Figure 26-3. Format of Option Byte (000C2H/010C2H)
Address: 000C2H/010C2H^Note
7
6
5
4
3
2
1
0
1
1
1
1
1
1
1
1
Note Be sure to set FFH to 000C2H, as these addresses are reserved areas. Also set FFH to 010C2H when the boot
swap operation is used because 000C2H is replaced by 010C2H.
26.3 Format of On-chip Debug Option Byte
The format of on-chip debug option byte is shown below.
Figure 26-4. Format of On-chip Debug Option Byte (000C3H/010C3H)
Address: 000C3H/010C3H^Note
7
6
5
4
3
2
1
OCDENSET
0
0
0
0
1
0
0
OCDERSD
OCDENSET
0
0
1
1
OCDERSD
0
1
0
1
Control of on-chip debug operation
Disables on-chip debug operation.
Setting prohibited
Erases data of flash memory in case of failures in enabling on-chip debugging and
authenticating on-chip debug security ID.
Does not erases data of flash memory in case of failures in enabling on-chip
debugging and authenticating on-chip debug security ID.
Note Set the same value as 000C3H to 010C3H when the boot swap operation is used because 000C3H is replaced
by 010C3H.
Caution Bits 7 and 0 (OCDENSET and OCDERSD) can only be specified a value.
Be sure to set 000010B to bits 6 to 1.
Remark The value on bits 3 to 1 will be written over when the on-chip debug function is in use and thus it will become
unstable after the setting.
However, be sure to set the default values (0, 1, and 0) to bits 3 to 1 at setting.
R01UH0004EJ0501 Rev.5.01
832
Jun 20, 2011