PIC16F877-20/L Microchip Technology, PIC16F877-20/L Datasheet - Page 54

• Manufacturer Part Number: PIC16F877-20/L
• Description: IC MCU FLASH 8KX14 EE 44PLCC
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F877-20/L

• Program Memory Type: FLASH
• Program Memory Size: 14KB (8K x 14)
• Package / Case: 44-PLCC
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Eeprom Size: 256 x 8
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: External
• Operating Temperature: 0°C ~ 70°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 368 B
• Interface Type: MSSP/PSP/USART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 33
• Number Of Timers: 3
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, ICE2000, DM163022, DV164120
• Minimum Operating Temperature: 0 C
• On-chip Adc: 8-ch x 10-bit
• Data Rom Size: 256 B
• Height: 3.87 mm
• Length: 16.59 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 4 V
• Width: 16.59 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164309 - MODULE SKT FOR PM3 44PLCC444-1001 - DEMO BOARD FOR PICMICRO MCUDVA16XL441 - ADAPTER DEVICE ICE 44PLCC309-1040 - ADAPTER 44-PLCC ZIF TO 40-DIP309-1039 - ADAPTER 44-PLCC TO 40-DIPDV007003 - PROGRAMMER UNIVERSAL PROMATE II
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC16F87X
6.1
Timer mode is selected by clearing the TMR1CS
(T1CON<1>) bit. In this mode, the input clock to the
timer is F
(T1CON<2>) has no effect, since the internal clock is
always in sync.
FIGURE 6-1:
6.3
Counter mode is selected by setting bit TMR1CS. In
this mode, the timer increments on every rising edge of
clock input on pin RC1/T1OSI/CCP2, when bit
T1OSCEN is set, or on pin RC0/T1OSO/T1CKI, when
bit T1OSCEN is cleared.
FIGURE 6-2:
DS30292C-page 52
T1CKI
(Default High)
T1CKI
(Default Low)
Note: Arrows indicate counter increments.
Note 1: When the T1OSCEN bit is cleared, the inverter is turned off. This eliminates power drain.
RC0/T1OSO/T1CKI
RC1/T1OSI/CCP2
Timer1 Operation in Timer Mode
Timer1 Operation in Synchronized
Counter Mode
OSC
/4. The synchronize control bit T1SYNC
Set Flag bit
TMR1IF on
Overflow
TIMER1 INCREMENTING EDGE
TIMER1 BLOCK DIAGRAM
(2)
TMR1H
T1OSC
TMR1
TMR1L
Oscillator
Enable
T1OSCEN
(1)
Clock
Internal
F
OSC
/4
TMR1ON
6.2
Timer1 may operate in either a Synchronous, or an
Asynchronous mode, depending on the setting of the
TMR1CS bit.
When Timer1 is being incremented via an external
source, increments occur on a rising edge. After Timer1
is enabled in Counter mode, the module must first have
a falling edge before the counter begins to increment.
If T1SYNC is cleared, then the external clock input is
synchronized with internal phase clocks. The synchro-
nization is done after the prescaler stage. The
prescaler stage is an asynchronous ripple-counter.
In this configuration, during SLEEP mode, Timer1 will
not increment even if the external clock is present,
since the synchronization circuit is shut-off. The
prescaler, however, will continue to increment.
On/Off
TMR1CS
1
0
Timer1 Counter Operation
T1CKPS1:T1CKPS0
T1SYNC
Prescaler
1, 2, 4, 8
0
1
2
2001 Microchip Technology Inc.
Synchronized
Clock Input
Synchronize
Q Clock
det