UPD75218 NEC, UPD75218 Datasheet - Page 17

• Manufacturer Part Number: UPD75218
• Description: 4-BIT SINGLE-CHIP MICROCOMPUTER
• Manufacturer: NEC

5.3
Note
The basic interval timer has the following functions:
• Interval timer operation to generate reference time
• Watchdog timer application to detect inadvertent program loop
• Wait time select and count upon standby mode release
• Count contents read
SET1
BASIC INTERVAL TIMER
From clock
generator
f
Note
Instruction execution
f
f
f
XX
BTM3
XX
XX
XX
/2
/2
/2
/2
12
5
7
9
BTM2
4
BTM1
MPX
3
BTM0
Fig. 5-2 Basic Interval Timer Configuration
BTM
Internal bus
Basic interval timer
(8-bit frequency divider)
8
Clear
BT
Wait release
signal during
standby release
Set
BT interrupt
request flag
IRQBT
Clear
PD75218
Vectored
interrupt
request
signal
17