PIC16C558/JW Microchip Technology, PIC16C558/JW Datasheet - Page 53
![IC MCU EPROM 2KX14 18CDIP](/photos/12/13/121351/150-18-cdip_sml.jpg)
PIC16C558/JW
Manufacturer Part Number
PIC16C558/JW
Description
IC MCU EPROM 2KX14 18CDIP
Manufacturer
Microchip Technology
Series
PIC® 16Cr
Specifications of PIC16C558/JW
Core Processor
PIC
Core Size
8-Bit
Speed
20MHz
Peripherals
POR, WDT
Number Of I /o
13
Program Memory Size
3.5KB (2K x 14)
Program Memory Type
EPROM, UV
Ram Size
128 x 8
Voltage - Supply (vcc/vdd)
2.5 V ~ 5.5 V
Oscillator Type
External
Operating Temperature
0°C ~ 70°C
Package / Case
18-CDIP (0.300", 7.62mm) Window
For Use With
ISPICR1 - ADAPTER IN-CIRCUIT PROGRAMMINGDVA16XP180 - ADAPTER DEVICE FOR MPLAB-ICEAC164010 - MODULE SKT PROMATEII DIP/SOIC
Lead Free Status / RoHS Status
Contains lead / RoHS non-compliant
Eeprom Size
-
Data Converters
-
Connectivity
-
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
7.3.1
The prescaler assignment is fully under software
control (i.e., it can be changed “on the fly” during
program execution). To avoid an unintended device
RESET,
(Example 7-1) must be executed when changing the
prescaler assignment from Timer0 to WDT. Lines 5-7
are required only if the desired postscaler rate is 1:1
(PS<2:0> = 000) or 1:2 (PS<2:0> = 001).
EXAMPLE 7-1:
TABLE 7-1:
2002 Microchip Technology Inc.
01h
0Bh/8Bh
81h
85h
Legend:
Note
Address
BCF
CLRF
BSF
MOVLW '00101111’b ;These 3 lines (5, 6, 7)
MOVWF OPTION
MOVLW '00101xxx’b ;Set Postscaler to
MOVWF OPTION
BCF
1:
TMR0
INTCON
OPTION
TRISA
STATUS, RP0 ;Skip if already in
TMR0
STATUS, RP0 ;Bank 1
STATUS, RP0 ;Return to Bank 0
— = Unimplemented locations, read as ‘0’,
Shaded bits are not used by TMR0 module.
Name
the
SWITCHING PRESCALER
ASSIGNMENT
REGISTERS ASSOCIATED WITH TIMER0
following
Timer0 module’s register
RBPU
Bit 7
GIE
—
CHANGING PRESCALER
(TIMER0→WDT)
;Bank 0 CLRWDT Clear WDT
;Clear TMR0 & Prescaler
;Are required only if
;Desired PS<2:0> are
;CLRWDT 000 or 001
;Desired WDT rate
Reserved
INTEDG
Bit 6
instruction
—
T0CS
Bit 5
T0IE
—
sequence
TRISA4
T0SE
INTE
Bit 4
Preliminary
TRISA3
RBIE
Bit 3
PSA
To change prescaler from the WDT to the TMR0
module use the sequence shown in Example 7-2. This
precaution must be taken even if the WDT is disabled.
EXAMPLE 7-2:
TRISA2
Bit 2
T0IF
PS2
CLRWDT
BSF
MOVLW
MOVWF
BCF
TRISA1
INTF
Bit 1
PS1
STATUS, RP0
b'xxxx0xxx' ;Select TMR0, new
OPTION
STATUS, RP0
TRISA0
RBIF
Bit 0
PS0
CHANGING PRESCALER
(WDT→TIMER0)
PIC16C55X
;Clear WDT and
;prescaler
;prescale value and
;clock source
xxxx xxxx
0000 000x
1111 1111
---1 1111
Value on
POR
DS40143D-page 51
uuuu uuuu
0000 000x
1111 1111
---1 1111
Value on
All Other
RESETS