PIC16F526-I/P Microchip Technology, PIC16F526-I/P Datasheet - Page 40

• Manufacturer Part Number: PIC16F526-I/P
• Description: IC PIC MCU FLASH 1KX12 14DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F526-I/P

• Program Memory Type: FLASH
• Program Memory Size: 1.5KB (1K x 12)
• Package / Case: 14-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Peripherals: POR, WDT
• Number Of I /o: 11
• Ram Size: 67 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 3x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 67 B
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 1
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit, 3 Channel
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC162096 - HEADER MPLAB ICD2 PIC16F526 8/14
• Eeprom Size: -
• Connectivity: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC16F526
7.2
An 8-bit counter is available as a prescaler for the
Timer0 module or as a postscaler for the Watchdog
Timer (WDT), respectively (see Section 8.6 “Watch-
dog Timer (WDT)”). For simplicity, this counter is
being referred to as “prescaler” throughout this data
sheet.
The PSA and PS<2:0> bits of the OPTION register
determine prescaler assignment and prescale ratio.
When assigned to the Timer0 module, all instructions
writing to the TMR0 register (e.g., CLRF TMR0,
MOVWF TMR0,
assigned to WDT, a CLRWDT instruction will clear the
prescaler along with the WDT. The prescaler is neither
readable nor writable. On a Reset, the prescaler
contains all ‘0’s.
7.2.1
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, the following instruction sequence (Example 7-
1) must be executed when changing the prescaler
assignment from Timer0 to the WDT.
DS41326E-page 40
Note:
Prescaler
The prescaler may be used by either the
Timer0 module or the WDT, but not both.
Thus, a prescaler assignment for the
Timer0 module means that there is no
prescaler for the WDT and vice versa.
SWITCHING PRESCALER
ASSIGNMENT
etc.) will clear the prescaler. When
EXAMPLE 7-1:
To change the prescaler from the WDT to the Timer0
module, use the sequence shown in Example 7-2. This
sequence must be used even if the WDT is disabled. A
CLRWDT instruction should be executed before
switching the prescaler.
EXAMPLE 7-2:
CLRWDT
CLRF
MOVLW
CLRWDT
MOVLW
OPTION
CLRWDT
MOVLW
OPTION
TMR0
b'00xx1111'
b'00xx1xxx' ;Set Postscaler to
b'xxxx0xxx' ;Select TMR0, new
CHANGING PRESCALER
(TIMER0 WDT)
CHANGING PRESCALER
(WDT TIMER0)
;Clear WDT
;Clear TMR0 & Prescaler
;PS<2:0> are 000 or 001
;desired WDT rate
 2010 Microchip Technology Inc.
;Clear WDT and
;prescaler
;prescale value and
;clock source