PIC16C72-04I/SO Microchip Technology, PIC16C72-04I/SO Datasheet - Page 69

• Manufacturer Part Number: PIC16C72-04I/SO
• Description: IC MCU OTP 2KX14 A/D PWM 28SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16C72-04I/SO

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 3.5KB (2K x 14)
• Program Memory Type: OTP
• Ram Size: 128 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 6 V
• Data Converters: A/D 5x8b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• For Use With: XLT28SO-1 - SOCKET TRANSITION 28SOIC 300MIL309-1024 - ADAPTER 28-SOIC TO 28-DIP309-1023 - ADAPTER 28-SOIC TO 28-DIP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

10.11
During an interrupt, only the return PC value is saved
on the stack. Typically, users may wish to save key reg-
isters during an interrupt, i.e., W register and STATUS
register. This will have to be implemented in software.
Example 10-1 stores and restores the W and STATUS
registers. The register, W_TEMP, must be defined in
each bank and must be defined at the same offset from
the bank base address (i.e., if W_TEMP is defined at
0x20 in bank 0, it must also be defined at 0xA0 in bank
1).
EXAMPLE 10-1: SAVING STATUS, W, AND PCLATH REGISTERS IN RAM
1998 Microchip Technology Inc.
MOVWF
SWAPF
CLRF
MOVWF
:
:Interrupt Service Routine (ISR) - user defined
:
SWAPF
MOVWF
SWAPF
SWAPF
Context Saving During Interrupts
W_TEMP
STATUS,W
STATUS
STATUS_TEMP
STATUS_TEMP,W
STATUS
W_TEMP,F
W_TEMP,W
;Copy W to W_TEMP register, could be bank one or zero
;Swap status to be saved into W
;bank 0, regardless of current bank, Clears IRP,RP1,RP0
;Save status to bank zero STATUS_TEMP register
;Swap STATUS_TEMP register into W
;(sets bank to original state)
;Move W into STATUS register
;Swap W_TEMP
;Swap W_TEMP into W
Preliminary
The example:
a)
b)
c)
d)
e)
Stores the W register.
Stores the STATUS register in bank 0.
Executes the ISR code.
Restores the STATUS register (and bank select
bit).
Restores the W register.
PIC16C72 Series
DS39016A-page 69