PIC16F73-I/SO Microchip Technology Inc., PIC16F73-I/SO Datasheet - Page 46

• Manufacturer Part Number: PIC16F73-I/SO
• Description: 28 PIN, 7 KB FLASH, 192 RAM, 22 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F73-I/SO

• A/d Inputs: 5-Channel, 8-Bit
• Cpu Speed: 5 MIPS
• Eeprom Memory: 0 Bytes
• Input Output: 22
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin SOIC
• 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

PIC16F7X
5.2
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
REGISTER 5-1:
DS30325B-page 44
Using Timer0 with an External
Clock
bit 7
bit 6
bit 5
bit 4
bit 3
bit 2-0
OPTION_REG REGISTER
Bit Value
bit 7
RBPU: PORTB Pull-up Enable bit (see Section 2.2.2.2)
INTEDG: Interrupt Edge Select bit (see Section 2.2.2.2)
T0CS: TMR0 Clock Source Select bit
1 = Transition on T0CKI pin
0 = Internal instruction cycle clock (CLKOUT)
T0SE: TMR0 Source Edge Select bit
1 = Increment on high-to-low transition on T0CKI pin
0 = Increment on low-to-high transition on T0CKI pin
PSA: Prescaler Assignment bit
1 = Prescaler is assigned to the WDT
0 = Prescaler is assigned to the Timer0 module
PS2:PS0: Prescaler Rate Select bits
Legend:
R = Readable bit
- n = Value at POR reset
Note:
R/W-1
RBPU
000
001
010
011
100
101
110
111
To avoid an unintended device RESET, the instruction sequences shown in
Example 5-1 and Example 5-2 (page 45) must be executed when changing the pres-
caler assignment between Timer0 and the WDT. This sequence must be followed
even if the WDT is disabled.
TMR0 Rate
INTEDG
R/W-1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
1 : 256
WDT Rate
R/W-1
T0CS
1 : 1
1 : 2
1 : 4
1 : 8
1 : 16
1 : 32
1 : 64
1 : 128
W = Writable bit
’1’ = Bit is set
R/W-1
T0SE
Q4 cycles of the internal phase clocks. Therefore, it is
necessary for T0CKI to be high for at least 2Tosc (and
a small RC delay of 20 ns) and low for at least 2Tosc
(and a small RC delay of 20 ns). Refer to the electrical
specification of the desired device.
R/W-1
U = Unimplemented bit, read as ‘0’
’0’ = Bit is cleared
PSA
R/W-1
PS2
 2002 Microchip Technology Inc.
x = Bit is unknown
R/W-1
PS1
R/W-1
PS0
bit 0