st62t62b STMicroelectronics, st62t62b Datasheet - Page 24

• Manufacturer Part Number: st62t62b
• Description: 8-bit Otp/eprom Mcus With A/d Converter, Auto-reload Timer And Eeprom
• Manufacturer: STMicroelectronics

24
ST62T52B ST62T62B/E62B
DIGITAL WATCHDOG (Cont’d)
These instructions test the C bit and Reset the
MCU (i.e. disable the Watchdog) if the bit is set
(i.e. if the Watchdog is active), thus disabling the
Watchdog.
In all modes, a minimum of 28 instructions are ex-
ecuted after activation, before the Watchdog can
generate a Reset. Consequently, user software
should load the watchdog counter within the first
27 instructions following Watchdog activation
(software mode), or within the first 27 instructions
executed following a Reset (hardware activation).
It should be noted that when the GEN bit is low (in-
terrupts disabled), the NMI interrupt is active but
cannot cause a wake up from STOP/WAIT
modes.
Figure 15. Digital Watchdog Block Diagram
24/68
S
RSFF
RESET
Q
R
DB0
DB1.7
8
WRITE
DATA BUS
-2
LOAD
7
RESET
SET
Figure 14. A typical circuit making use of the
EXERNAL STOP MODE CONTROL feature
SWITCH
SET
-2
8
OSCILLATOR
CLOCK
-12
VA00010
NMI
I/O
VR02002