ST6246 STMICROELECTRONICS [STMicroelectronics], ST6246 Datasheet - Page 24
ST6246
Manufacturer Part Number
ST6246
Description
8-BIT OTP/EPROM MCU WITH LCD DRIVER, EEPROM AND A/D CONVERTER
Manufacturer
STMICROELECTRONICS [STMicroelectronics]
Datasheet
1.ST6246.pdf
(72 pages)
- Current page: 24 of 72
- Download datasheet (453Kb)
ST62T46B/E46B
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 3.3.1 Digital Watchdog Register (DWDR) .
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 inFigure 14.
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 384 s to 24.576ms).
24/72
360
Figure 14. Watchdog Counter Control
D0
D1
D2
D3
D4
D5
D6
D7
2
8
SR
T5
T4
T3
T2
T1
T0
C
OSC 12
RESET
VR02068A
Related parts for ST6246
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
HIGH VOLTAGE FAST-SWITCHING NPN POWER TRANSISTOR
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
(ST62T15C / ST62T25C) 8-BIT OTP/EPROM MCUs WITH A/D CONVERTER
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
(ST62E35B / ST62T35B) 8-BIT OTP/EPROM MCUs
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
8-BIT OTP/EPROM MCU WITH LCD DRIVER / EEPROM AND A/D CONVERTER
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
AUdio Amplifier
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
NPN MEDIUM POWER TRANSISTOR
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
(ST90135 / ST90158) Microcontroller
Manufacturer:
ST Microelectronics
Part Number:
Description:
(ST90x27 / ST90x28) 16K EPROM HCMOS MCUS WITH RAM
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
(ST90R28B6) 16K ROM / 256 RAM HCMOS MCUs
Manufacturer:
ST Microelectronics
Part Number:
Description:
(ST90x31) 8K EPROM HCMOS MCU
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
(ST92195C/D) 48-96 Kbyte ROM HCMOS MCU
Manufacturer:
ST Microelectronics
Part Number:
Description:
16-48K ROM HCMOS MCU WITH ON SCREEN DISPLAY AND VOLTAGE TUNINGOUTPUT
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
48K ROM HCMOS MCUs WITH ON SCREEN DISPLAY AND A/D CONVERTER
Manufacturer:
ST Microelectronics
Datasheet:
Part Number:
Description:
24K ROM HCMOS MCU WITH ON SCREEN DISPLAY AND CLOSED-CAPTION DATA SLICER
Manufacturer:
ST Microelectronics
Datasheet: