PIC16F688-E/P Microchip Technology, PIC16F688-E/P Datasheet - Page 175

• Manufacturer Part Number: PIC16F688-E/P
• Description: IC MCU PIC FLASH 4KX14 14DIP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F688-E/P

• Program Memory Type: FLASH
• Program Memory Size: 7KB (4K x 14)
• Package / Case: 14-DIP (0.300", 7.62mm)
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: UART/USART
• Peripherals: Brown-out Detect/Reset, POR, WDT
• Number Of I /o: 12
• Eeprom Size: 256 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 256 B
• Interface Type: SCI/USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 2
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 125 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, DM163014, DM164120-4
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8-ch x 10-bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC162066 - HEADER INTRFC MPLAB ICD2 20PINAC162061 - HEADER INTRFC MPLAB ICD2 20PINDM163029 - BOARD PICDEM FOR MECHATRONICSAC162056 - HEADER INTERFACE ICD2 16F688ACICE0207 - MPLABICE 14P 300 MIL ADAPTER
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

11.6
1997 Microchip Technology Inc.
T0CKI pin
CLKOUT (=Fosc/4)
WDT Enable bit
Watchdog
Note: T0CS, T0SE, PSA, PS2:PS0 are (OPTION_REG<5:0>).
Timer
TMR0 Prescaler
T0SE
An 8-bit counter is available as a prescaler for the Timer0 module, or as a postscaler for the
Watchdog Timer
the Timer0 description. Thus, a prescaler assignment for the Timer0 module means that there is
no postscaler for the Watchdog Timer, and vice-versa.
The PSA and PS2:PS0 bits (OPTION<3:0>) determine the prescaler assignment and prescale
ratio.
When assigned to the Timer0 module, all instructions writing to the TMR0 register (e.g.,
CLRF TMR0, MOVWF TMR0, BSF TMR0,x....etc.) will clear the prescaler. When assigned to WDT,
a CLRWDT instruction will clear the prescaler along with the Watchdog Timer. The prescaler is not
readable or writable.
Figure 11-6: Block Diagram of the Timer0/WDT Prescaler
Note:
0
1
PSA
M
U
X
There is only one prescaler available which is mutually exclusively shared between
the Timer0 module and the Watchdog Timer.
0
1
T0CS
(Figure
M
U
X
0
8-bit Prescaler
8 - to - 1MUX
11-6). For simplicity, this counter is being referred to as “prescaler” in
Time-out
8
M U X
WDT
1
0
1
PSA
M
U
X
PSA
Section 11. Timer0
PS2:PS0
Cycles
SYNC
2
TMR0 reg
Data Bus
8
DS31011A-page 11-7
Set T0IF flag bit
on Overflow
11