參數(shù)資料
型號: 35007B
廠商: Microchip Technology Inc.
英文描述: 18-pin Enhanced FLASH/EEPROM 8-bit Microcontroller
中文描述: 18針/ EEPROM的8位微控制器的閃存
文件頁數(shù): 32/88頁
文件大?。?/td> 1495K
代理商: 35007B
PIC16F84A
DS35007B-page 30
2001 Microchip Technology Inc.
6.9
Context Saving During Interrupts
During an interrupt, only the return PC value is saved
on the stack. Typically, users wish to save key register
values during an interrupt (e.g., W register and
STATUS register). This is implemented in software.
The code in Example 6-1 stores and restores the
STATUS and W register’s values. The user defined
registers, W_TEMP and STATUS_TEMP are the tem-
porary storage locations for the W and STATUS
registers values.
Example 6-1 does the following:
a)
Stores the W register.
b)
Stores the STATUS register in STATUS_TEMP.
c)
Executes the Interrupt Service Routine code.
d)
Restores the STATUS (and bank select bit)
register.
e)
Restores the W register.
EXAMPLE 6-1:
PUSH
SAVING STATUS AND W REGISTERS IN RAM
W_TEMP
; Copy W to TEMP register,
STATUS,
W
; Swap status to be saved into W
STATUS_TEMP
; Save status to STATUS_TEMP register
:
; Interrupt Service Routine
; should configure Bank as required
;
STATUS_TEMP,W
; Swap nibbles in STATUS_TEMP register
; and place result into W
STATUS
; Move W into STATUS register
; (sets bank to original state)
W_TEMP,
F
; Swap nibbles in W_TEMP and place result in W_TEMP
W_TEMP,
W
; Swap nibbles in W_TEMP and place result into W
6.10
Watchdog Timer (WDT)
The Watchdog Timer is a free running On-Chip RC
Oscillator which does not require any external
components. This RC oscillator is separate from the
RC oscillator of the OSC1/CLKIN pin. That means that
the WDT will run even if the clock on the OSC1/CLKIN
and OSC2/CLKOUT pins of the device has been
stopped, for example, by execution of a
SLEEP
instruction. During normal operation, a WDT time-out
generates a device RESET. If the device is in SLEEP
mode, a WDT wake-up causes the device to wake-up
and continue with normal operation. The WDT can be
permanently disabled by programming configuration bit
WDTE as a '0' (Section 6.1).
6.10.1
WDT PERIOD
The WDT has a nominal time-out period of 18 ms, (with
no prescaler). The time-out periods vary with
temperature, V
DD
and process variations from part to
part (see DC specs). If longer time-out periods are
desired, a prescaler with a division ratio of up to 1:128
can be assigned to the WDT under software control by
writing to the OPTION_REG register. Thus, time-out
periods up to 2.3 seconds can be realized.
The
CLRWDT
and
SLEEP
instructions clear the WDT
and the postscaler (if assigned to the WDT) and pre-
vent it from timing out and generating a device
RESETcondition.
The TO bit in the STATUS register will be cleared upon
a WDT time-out.
MOVWF
SWAPF
MOVWF
:
:
:
:
SWAPF
ISR
POP
MOVWF
SWAPF
SWAPF
相關(guān)PDF資料
PDF描述
350PJT 1200A ITGQ Gate Turn-Off Hockey Puk SCRs
351-90-116-00-017 PCB connectors 2.54 mm Single row / double row Solder tail
351-90-116-00-016 HOOD DB50 PLASTIC 10 PACK
351-90-116-00-005 DB-50 PLASTIC HOOD
351-90-116-00-004 CRIMP SHELLS DB50 FEMALE
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
35-007-BU 制造商:GC Electronics 功能描述:Switch Toggle ON OFF (ON) SPDT Bat Toggle Solder 5A 250VAC 28VDC Panel Mount with Threads Bulk
35008 功能描述:WRENCH OPEN END METRIC 10X11MM RoHS:否 類別:工具 >> 鉗子、扳手 系列:350 標準包裝:1 系列:- 尖端 - 類型:針頭,直形 工具類型:鉗子 特點:人機工程型手柄,ESD 安全,鋸齒狀 長度:5.75"(146.05mm) 重量:0.23 磅(104.33g)
35-008 制造商:GC Electronics 功能描述:SPDT(ON)-OFF-(ON)MIN BAT TO 制造商:Ideal Industries Inc 功能描述:TENITE HANDLES 8 IN 制造商:GC Electronics 功能描述:Switch Toggle (ON) OFF (ON) SPDT Bat Toggle Solder 5A 250VAC 28VDC Panel Mount with Threads 制造商:Ideal Industries Inc 功能描述:Switch Toggle (ON) OFF (ON) SPDT Bat Toggle
35008 BK199 制造商:Alpha Wire Company 功能描述:35008 BLACK 1000 = 1000 FT
350080-1 功能描述:端子 RING 18-14 10 .025TP RoHS:否 制造商:AVX 產(chǎn)品:Junction Box - Wire to Wire 系列:9826 線規(guī):26-18 接線柱/接頭大小: 絕緣: 顏色:Red 型式:Female 觸點電鍍:Tin over Nickel 觸點材料:Beryllium Copper, Phosphor Bronze 端接類型:Crimp