PIC16C925/CL Microchip Technology, PIC16C925/CL Datasheet - Page 111

• Manufacturer Part Number: PIC16C925/CL
• Description: IC MCU EPROM 4KX14 LCDDVR 68CLCC
• Manufacturer: Microchip Technology
• Series: PIC® 16Cr

Specifications of PIC16C925/CL

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 25
• Program Memory Size: 7KB (4K x 14)
• Program Memory Type: EPROM
• Ram Size: 176 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 68-CLCC Window, 68-CERQUAD
• For Use With: AC164308 - MODULE SKT FOR PM3 68PLCCDVA16XL680 - ADAPTER DEVICE FOR MPLAB-ICEAC164024 - ADAPTER PICSTART PLUS 68PLCCAC164022 - MODULE SKT PROMATEII 68PLCC
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

12.6
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., the W and STATUS reg-
isters. This will have to be implemented in software.
Example 12-1 stores and restores the STATUS, W, and
PCLATH 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 12-1:
2001 Microchip Technology Inc.
MOVWF
SWAPF
CLRF
MOVWF
MOVF
MOVWF
CLRF
BCF
MOVF
MOVWF
MOVF
MOVWF
SWAPF
MOVWF
SWAPF
SWAPF
Context Saving During Interrupts
:
:(ISR)
:
W_TEMP
STATUS,W
STATUS
STATUS_TEMP
PCLATH, W
PCLATH_TEMP
PCLATH
STATUS, IRP
FSR, W
FSR_TEMP
PCLATH_TEMP, W
PCLATH
STATUS_TEMP,W
STATUS
W_TEMP,F
W_TEMP,W
SAVING STATUS, W, AND PCLATH REGISTERS IN RAM
;Copy W to 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
;Only required if using pages 1, 2 and/or 3
;Save PCLATH into W
;Page zero, regardless of current page
;Return to Bank 0
;Copy FSR to W
;Copy FSR from W to FSR_TEMP
;Insert user code here
;Restore PCLATH
;Move W into PCLATH
;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 code in the example:
e)
f)
g)
h)
i)
j)
Stores the W register.
Stores the STATUS register in bank 0.
Stores the PCLATH register.
Executes the ISR code.
Restores the STATUS register (and bank select
bit).
Restores the W and PCLATH registers.
PIC16C925/926
DS39544A-page 109