PIC16F737-I/SP Microchip Technology Inc., PIC16F737-I/SP Datasheet - Page 76

• Manufacturer Part Number: PIC16F737-I/SP
• Description: 28 PIN, 7 KB FLASH, 368 RAM, 25 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F737-I/SP

• A/d Inputs: 5-Channel, 8-Bit
• Cpu Speed: 5 MIPS
• Eeprom Memory: 0 Bytes
• Input Output: 25
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin SPDIP
• Programmable Memory: 7K Bytes
• Ram Size: 192 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

PIC16F7X7
6.3
When no prescaler is used, the external clock input is
the same as the prescaler output. The synchronization
of T0CKI with the internal phase clocks is accom-
plished by sampling the prescaler output on the Q2 and
Q4 cycles of the internal phase clocks. Therefore, it is
necessary for T0CKI to be high for at least 2 T
a small RC delay of 20 ns) and low for at least 2 T
(and a small RC delay of 20 ns). Refer to the electrical
specification of the desired device.
6.4
There is only one prescaler available, which is mutually
exclusively shared between the Timer0 module and the
Watchdog Timer. A prescaler assignment for the
Timer0 module means that the prescaler cannot be
used by the Watchdog Timer and vice versa. This
prescaler is not readable or writable (see Figure 6-1).
DS30498C-page 74
Using Timer0 With an
External Clock
Prescaler
OSC
(and
OSC
The PSA and PS2:PS0 bits (OPTION_REG<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 1, MOVWF 1,
BSF 1,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.
Note:
Note:
Although the prescaler can be assigned to
either the WDT or Timer0, but not both, a
new divide counter is implemented in the
WDT circuit to give multiple WDT time-out
selections. This allows TMR0 and WDT to
each have their own scaler. Refer to
Section 15.17 “Watchdog Timer (WDT)”
for further details.
Writing to TMR0 when the prescaler is
assigned to Timer0 will clear the prescaler
count but will not change the prescaler
assignment.
 2004 Microchip Technology Inc.