ST72F264G2B6 STMicroelectronics, ST72F264G2B6 Datasheet - Page 51

• Manufacturer Part Number: ST72F264G2B6
• Description: MCU 8-BIT 8K FLASH 32-SDIP
• Manufacturer: STMicroelectronics
• Series: ST7r

Specifications of ST72F264G2B6

• Mfg Application Notes: ST7 Checksum Capability, AN1070 App Note
• Core Processor: ST7
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 6x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 32-SDIP (0.400", 10.16mm)
• Processor Series: ST72F2x
• Core: ST7
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: I2C, SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 3
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• Development Tools By Supplier: ST7F264-IND/USB, ST72F34X-SK/RAIS, ST7MDT10-DVP3, ST7MDT10-EMU3, STX-RLINK
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 6 Channel
• For Use With: 497-6423 - BOARD EVAL BASED ON ST72264G1497-5046 - KIT TOOL FOR ST7/UPSD/STR7 MCU
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details
• Other names: 497-5570

WATCHDOG TIMER (Cont’d)
11.1.5 Low Power Modes
11.1.6 Hardware Watchdog Option
If Hardware Watchdog is selected by option byte,
the watchdog is always active and the WDGA bit in
the WDGCR is not used. Refer to the Option Byte
description.
11.1.7 Using Halt Mode with the WDG
(WDGHALT option)
The following recommendation applies if Halt
mode is used when the watchdog is enabled.
– Before executing the HALT instruction, refresh
11.1.8 Interrupts
None.
the WDG counter, to avoid an unexpected WDG
reset immediately after waking up the microcon-
troller.
SLOW
Mode
WAIT
HALT
Description
No effect on Watchdog.
No effect on Watchdog.
OIE bit in
MCCSR
register
0
0
1
WDGHALT bit
in Option
Byte
0
1
x
No Watchdog reset is generated. The MCU enters Halt mode. The Watch-
dog counter is decremented once and then stops counting and is no longer
able to generate a watchdog reset until the MCU receives an external inter-
rupt or a reset.
If an external interrupt is received, the Watchdog restarts counting after 256
or 4096 CPU clocks. If a reset is generated, the Watchdog is disabled (reset
state) unless Hardware Watchdog is selected by option byte. For applica-
tion recommendations see
A reset is generated.
No reset is generated. The MCU enters Active Halt mode. The Watchdog
counter is not decremented. It stop counting. When the MCU receives an
oscillator interrupt or external interrupt, the Watchdog restarts counting im-
mediately. When the MCU receives a reset the Watchdog restarts counting
after 256 or 4096 CPU clocks.
11.1.9 Register Description
CONTROL REGISTER (WDGCR)
Read/Write
Reset Value: 0111 1111 (7Fh)
Bit 7 = WDGA Activation bit.
This bit is set by software and only cleared by
hardware after a reset. When WDGA = 1, the
watchdog can generate a reset.
0: Watchdog disabled
1: Watchdog enabled
Note: This bit is not used if the hardware watch-
dog option is enabled by option byte.
Bit 6:0 = T[6:0] 7-bit counter (MSB to LSB).
These bits contain the value of the watchdog
counter. It is decremented every 16384 f
cles (approx.). A reset is produced when it rolls
over from 40h to 3Fh (T6 becomes cleared).
WDGA
7
ST72260Gx, ST72262Gx, ST72264Gx
Section 11.1.7
T6
T5
below.
T4
T3
T2
T1
OSC2
51/172
T0
0
cy-