ST62T65CB6 STMicroelectronics, ST62T65CB6 Datasheet - Page 27

• Manufacturer Part Number: ST62T65CB6
• Description: IC MCU 8BIT W/ADC 28-PDIP
• Manufacturer: STMicroelectronics
• Series: ST6r

Specifications of ST62T65CB6

• Core Processor: ST6
• Core Size: 8-Bit
• Speed: 8MHz
• Connectivity: SPI
• Peripherals: LED, LVD, POR, WDT
• Number Of I /o: 21
• Program Memory Size: 3.8KB (3.8K x 8)
• Program Memory Type: OTP
• Eeprom Size: 128 x 8
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 6 V
• Data Converters: A/D 13x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-DIP (0.600", 15.24mm)
• Processor Series: ST62T6x
• Core: ST6
• Data Bus Width: 8 bit
• Data Ram Size: 128 B
• Interface Type: SCI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 21
• Number Of Timers: 1
• Operating Supply Voltage: 3 V to 6 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: Through Hole
• Development Tools By Supplier: ST62GP-EMU2, ST62E2XC-EPB/110, ST62E6XC-EPB/US, STREALIZER-II
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

DIGITAL WATCHDOG (Cont’d)
The Watchdog is associated with a Data space
register (Digital WatchDog Register, DWDR, loca-
tion 0D8h) which is described in greater detail in
Section 3.2.1 Digital Watchdog Register
This register is set to 0FEh on Reset: bit C is
cleared to “0”, which disables the Watchdog; the
timer downcounter bits, T0 to T5, and the SR bit
are all set to “1”, thus selecting the longest Watch-
dog timer period. This time period can be set to the
user’s requirements by setting the appropriate val-
ue for bits T0 to T5 in the DWDR register. The SR
bit must be set to “1”, since it is this bit which gen-
erates the Reset signal when it changes to “0”;
clearing this bit would generate an immediate Re-
set.
It should be noted that the order of the bits in the
DWDR register is inverted with respect to the as-
sociated bits in the down counter: bit 7 of the
DWDR register corresponds, in fact, to T0 and bit
2 to T5. The user should bear in mind the fact that
these bits are inverted and shifted with respect to
the physical counter bits when writing to this regis-
ter. The relationship between the DWDR register
bits and the physical implementation of the Watch-
dog timer downcounter is illustrated in
Only the 6 most significant bits may be used to de-
fine the time period, since it is bit 6 which triggers
the Reset when it changes to “0”. This offers the
user a choice of 64 timed periods ranging from
3,072 to 196,608 clock cycles (with an oscillator
frequency of 8MHz, this is equivalent to timer peri-
ods ranging from 384µs to 24.576ms).
Figure
(DWDR).
17.
Figure 17. Watchdog Counter Control
D0
D1
D2
D3
D4
D5
D6
D7
ST6255C ST6265C ST6265B
2
8
SR
T5
T4
T3
T2
T1
T0
C
OSC 12
RESET
VR02068A
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