参数资料
型号: ST62E45BG1
元件分类: 8位微控制器
英文描述: 8-BIT MICROCONTROLLER
中文描述: 8位微控制器
文件页数: 21/74页
文件大小: 733K
代理商: ST62E45BG1
21/74
ST62T46B/E46B
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 V
DD
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 V
DD
. The typical threshold is in the region
of 2 volts, but the actual value of the detected
threshold depends on the way in which V
DD
rises.
The POR circuit is
NOT
designed to supervise
static, or slowly rising or falling V
DD
.
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 12. Reset and Interrupt Processing
Figure 13. Reset Block Diagram
RESET
RESET
VECTOR
JP
JP:2 BYTES/4 CYCLES
RETI
RETI: 1 BYTE/2 CYCLES
INITIALIZATION
ROUTINE
VA00181
V
DD
RESET
300k
2.8k
POWER
WATCHDOG RESET
CK
COUNTER
RESET
ST6
INTERNAL
RESET
f
OSC
RESET
ON RESET
VA0200B
相关PDF资料
PDF描述
ST62T40BQ6 8-BIT MICROCONTROLLER
ST62T42BQ6 8-BIT MICROCONTROLLER ( MCU ) WITH OTP. ROM. FASTROM. EPROM. LCD DRIVER. EEPROM. A/D CONVERTER AND 64 PINS
ST624XB-DBE REAL TIME EMULATION DEVELOPMENT TOOLS FOR ST6 MCU FAMILY
ST6263C 8-BIT MICROCONTROLLER ( MCU ) WITH OTP. ROM. FASTROM. EPROM. A/D CONVERTER. SAFE RESET. AUTO-RELOAD TIMER. EEPROM AND SPI
ST6265C 8-BIT MICROCONTROLLER ( MCU ) WITH OTP. ROM. FASTROM. EPROM. A/D CONVERTER. SAFE RESET. AUTO-RELOAD TIMER. EEPROM AND SPI
相关代理商/技术参数
参数描述
ST62E45G1 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller
ST62E46 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:EPROM PROGRAMMING BOARDS FOR ST62 MCU FAMILY
ST62E46B 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8-BIT OTP/EPROM MCU WITH LCD DRIVER, EEPROM AND A/D CONVERTER
ST62E46BF1 功能描述:8位微控制器 -MCU UV EPROM 4K SPI RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
ST62E4X 制造商:STMICROELECTRONICS 制造商全称:STMicroelectronics 功能描述:8/16-Bit Micros