PIC12F683-I/SN Microchip Technology Inc., PIC12F683-I/SN Datasheet - Page 37

• Manufacturer Part Number: PIC12F683-I/SN
• Description: 8 PIN, 3.5 KB FLASH, 128 RAM, 6 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC12F683-I/SN

• A/d Inputs: 4-Channel, 10-Bit
• Comparators: 1
• Cpu Speed: 5 MIPS
• Eeprom Memory: 256 Bytes
• Input Output: 5
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 8-pin SOIC-N
• Programmable Memory: 3.5K Bytes
• Ram Size: 128 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

4.2.4
The Ultra Low-Power Wake-up (ULPWU) on GP0
allows a slow falling voltage to generate an inter-
rupt-on-change on GP0 without excess current con-
sumption. The mode is selected by setting the
ULPWUE bit of the PCON register. This enables a
small current sink which can be used to discharge a
capacitor on GP0.
To use this feature, the GP0 pin is configured to output
‘1’ to charge the capacitor, interrupt-on-change for GP0
is enabled and GP0 is configured as an input. The ULP-
WUE bit is set to begin the discharge and a SLEEP
instruction is performed. When the voltage on GP0
drops below V
cause the device to wake-up. Depending on the state of
the GIE bit of the INTCON register, the device will either
jump to the interrupt vector (0004h) or execute the next
instruction when the interrupt event occurs. See
Section 4.2.3
Section 12.4.3 “GPIO Interrupt” for more information.
This feature provides a low-power technique for period-
ically waking up the device from Sleep. The time-out is
dependent on the discharge time of the RC circuit
on GP0. See Example 4-2 for initializing the Ultra
Low-Power Wake-up module.
The series resistor provides overcurrent protection for
the GP0 pin and can allow for software calibration of the
time-out (see Figure 4-1). A timer can be used to mea-
sure the charge time and discharge time of the capaci-
tor. The charge time can then be adjusted to provide the
desired interrupt delay. This technique will compensate
for the affects of temperature, voltage and component
accuracy. The Ultra Low-Power Wake-up peripheral
can also be configured as a simple Programmable
Low-Voltage Detect or temperature sensor.
© 2006 Microchip Technology Inc.
ULTRA LOW-POWER WAKE-UP
IL
, an interrupt will be generated which will
“Interrupt-on-Change”
and
EXAMPLE 4-2:
BANKSEL
MOVLW
MOVWF
BANKSEL
BCF
BCF
BANKSEL
BSF
CALL
BANKSEL
BSF
BSF
BSF
MOVLW
MOVWF
SLEEP
NOP
Note:
For more information, refer to the Applica-
tion Note AN879, “Using the Microchip
Ultra
(DS00879).
CMCON0
H’7’
CMCON0
ANSEL
ANSEL,0
TRISA,0
PORTA
PORTA,0
CapDelay
PCON
PCON,ULPWUE ;Enable ULP Wake-up
IOCA,0
TRISA,0
B’10001000’ ;Enable interrupt
INTCON
Low-Power
ULTRA LOW-POWER
WAKE-UP INITIALIZATION
PIC12F683
;
;Turn off
;comparators
;
;RA0 to digital I/O
;Output high to
;
;charge capacitor
;
;
;Select RA0 IOC
;RA0 to input
; and clear flag
;Wait for IOC
;
Wake-up
DS41211C-page 35
Module”