ST72T213G1B6 STMicroelectronics, ST72T213G1B6 Datasheet - Page 30

• Manufacturer Part Number: ST72T213G1B6
• Description: 8-bit Microcontrollers - MCU OTP EPROM 4K SPI
• Manufacturer: STMicroelectronics

Specifications of ST72T213G1B6

• Rohs: yes
• Core: ST7
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 8 MHz
• Program Memory Size: 4 KB
• Data Ram Size: 256 B
• On-chip Adc: Yes
• Operating Supply Voltage: 3 V to 5.5 V
• Package / Case: PDIP-32
• Mounting Style: Through Hole
• A/d Bit Size: 8 bit
• A/d Channels Available: 6
• Interface Type: SPI
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 22
• Number Of Timers: 1
• On-chip Dac: No
• Program Memory Type: OTP EPROM
• Factory Pack Quantity: 16
• Supply Voltage - Max: 5.5 V
• Supply Voltage - Min: 3.5 V

ST72101/ST72212/ST72213
5.2 WATCHDOG TIMER (WDG)
5.2.1 Introduction
The Watchdog timer is used to detect the occur-
rence of a software fault, usually generated by ex-
ternal interference or by unforeseen logical condi-
tions, which causes the application program to
abandon its normal sequence. The Watchdog cir-
cuit generates an MCU reset on expiry of a pro-
grammed time period, unless the program refresh-
es the counter’s contents before the T6 bit be-
comes cleared.
Figure 21. Watchdog Block Diagram
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30
f
CPU
WDGA
RESET
T6
T5
WATCHDOG CONTROL REGISTER (CR)
7-BIT DOWNCOUNTER
CLOCK DIVIDER
T4
12288
T3
5.2.2 Main Features
T2
Programmable timer (64 increments of 12288
CPU cycles)
Programmable reset
Reset (if watchdog activated) after a HALT
instruction or when the T6 bit reaches zero
T1
T0