参数资料
型号: ST6232BQ3/XXX
厂商: STMICROELECTRONICS
元件分类: 微控制器/微处理器
英文描述: 8-BIT, MROM, 4 MHz, MICROCONTROLLER, PQFP42
封装: PLASTIC, QFP-52
文件页数: 16/83页
文件大小: 1815K
代理商: ST6232BQ3/XXX
Obsolete
Product(s)
- Obsolete
Product(s)
Obsolete
Product(s)
- Obsolete
Product(s)
23/83
ST62T32B ST62E32B
RESETS (Cont’d)
3.2.3 Watchdog Reset
The MCU provides a Watchdog timer function in
order to ensure graceful recovery from software
upsets. If the Watchdog register is not refreshed
before an end-of-count condition is reached, the
internal reset will be activated. This, amongst oth-
er things, resets the watchdog counter.
The MCU restarts just as though the Reset had
been generated by the RESET pin, including the
built-in stabilisation delay period.
3.2.4 Application Notes
No external resistor is required between VDD and
the Reset pin, thanks to the built-in pull-up device.
The POR circuit operates dynamically, in that it
triggers MCU initialization on detecting the rising
edge of VDD. The typical threshold is in the region
of 2 volts, but the actual value of the detected
threshold depends on the way in which VDD rises.
The POR circuit is
NOT designed to supervise
static, or slowly rising or falling VDD.
3.2.5 MCU Initialization Sequence
When a reset occurs the stack is reset, the PC is
loaded with the address of the Reset Vector (locat-
ed in program ROM starting at address 0FFEh). A
jump to the beginning of the user program must be
coded at this address. Following a Reset, the In-
terrupt flag is automatically set, so that the CPU is
in Non Maskable Interrupt mode; this prevents the
initialisation routine from being interrupted. The in-
itialisation routine should therefore be terminated
by a RETI instruction, in order to revert to normal
mode and enable interrupts. If no pending interrupt
is present at the end of the initialisation routine, the
MCU will continue by processing the instruction
immediately following the RETI instruction. If, how-
ever, a pending interrupt is present, it will be serv-
iced.
Figure 15. Reset and Interrupt Processing
Figure 16. Reset Block Diagram
RESET
VECTOR
JP
JP:2 BYTES/4 CYCLES
RETI
RETI: 1 BYTE/2 CYCLES
INITIALIZATION
ROUTINE
VA00181
VDD
RESET
300k
2.8k
POWER
WATCHDOG RESET
CK
COUNTER
RESET
ST6
INTERNAL
RESET
fOSC
RESET
ON RESET
VA0200B
相关PDF资料
PDF描述
ST62T52BB6 8-BIT, OTPROM, 8 MHz, MICROCONTROLLER, PDIP16
ST62T62CB6 8-BIT, OTPROM, 8 MHz, MICROCONTROLLER, PDIP16
ST62T52CN6 8-BIT, OTPROM, 8 MHz, MICROCONTROLLER, PDSO16
ST62E62CF1 8-BIT, UVPROM, 8 MHz, MICROCONTROLLER, CDIP16
ST62P62CN6/XXX 8-BIT, MROM, 8 MHz, MICROCONTROLLER, PDSO16
相关代理商/技术参数
参数描述
ST6232BQ6 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-BIT OTP/EPROM MCUs WITH A/D CONVERTER, 16-BIT AUTO-RELOAD TIMER, EEPROM, SPI AND UART
ST6232BQ6/XXX 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller
ST6235BQ1 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-BIT OTP/EPROM MCUs WITH A/D CONVERTER, 16-BIT AUTO-RELOAD TIMER, EEPROM, SPI AND UART
ST6235BQ1/XXX 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller
ST6235BQ3 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-BIT OTP/EPROM MCUs WITH A/D CONVERTER, 16-BIT AUTO-RELOAD TIMER, EEPROM, SPI AND UART