UPD78F0890GK(A)-GAJ-AX NEC, UPD78F0890GK(A)-GAJ-AX Datasheet - Page 595

• Manufacturer Part Number: UPD78F0890GK(A)-GAJ-AX
• Description: 8BIT MCU, 128K FLASH, 7K RAM, LQFP
• Manufacturer: NEC

Specifications of UPD78F0890GK(A)-GAJ-AX

• Controller Family/series: UPD78F
• No. Of I/o's: 55
• Ram Memory Size: 7KB
• Cpu Speed: 20MHz
• No. Of Timers: 10
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 128KB
• Oscillator Type: External, Internal

23.1 Functions of Option Bytes
the device is restarted from the reset status, the device automatically references the option bytes and sets specified
functions. When using the product, be sure to set the following functions by using the option bytes.
Therefore, set values that are the same as those of 0080H to 0084H to 1080H to 1084H in advance.
(1) 0080H/1080H
(2) 0081H/1081H
The flash memory at 0080H to 0084H of the 78K0/FE2 is an option byte area. When power is turned on or when
When the boot swap operation is used during self-programming, 0080H to 0084H are switched to 1080H to 1084H.
Caution Be sure to set 00H to 0082H and 0083H (0082H/1082H and 0083H/1083H when the boot swap
Internal low-speed oscillator operation
• Can be stopped by software
• Cannot be stopped
Watchdog timer interval time setting
Watchdog timer counter operation
• Enabled counter operation
• Disabled counter operation
Watchdog timer window open period setting
Caution Set a value that is the same as that of 0080H to 1080H because 0080H and 1080H are
Selecting POC mode
• During 2.7 V/1.59 V POC mode operation (LVISTART = 1)
• During 1.59 V POC mode operation (LVISTART = 0)
Caution LVISTART can only be written by using a dedicated flash memory programmer. It cannot be
The device is in the reset state upon power application and until the supply voltage reaches 2.7 V (TYP.). It
is released from the reset state when the voltage exceeds 2.7 V (TYP.). After that, POC is not detected at
2.7 V but is detected at 1.59 V (TYP.).
If the supply voltage rises to 1.8 V after power application at a pace slower than 0.5 V/ms (MIN.), use of the
2.7 V/1.59 V POC mode is recommended.
The device is in the reset state upon power application and until the supply voltage reaches 1.59 V (TYP.).
It is released from the reset state when the voltage exceeds 1.59 V (TYP.). After that, POC is detected at
1.59 V (TYP.), in the same manner as on power application.
function is used).
switched during the boot swap operation.
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.
CHAPTER 23 OPTION BYTE
User’s Manual U17554EJ4V0UD
595