Datasheet

PIC16F8X
DS30430B-page 116
1996 Microchip Technology Inc.
Overflows....................................................................18
Underflows..................................................................18
STATUS....................................................................7, 15, 43
T
Time-out..............................................................................43
Timer0
Switching Prescaler Assignment.................................31
T0IF.............................................................................49
Timer0 Module............................................................27
TMR0 Interrupt............................................................49
TMR0 with External Clock...........................................29
Timing Diagrams
Time-out Sequence.....................................................45
Timing Diagrams and Specifications.............................78, 92
TRISA..................................................................................21
TRISB............................................................................23, 43
W
W.........................................................................................43
Wake-up from SLEEP...................................................43, 52
Watchdog Timer (WDT) ....................................37, 42, 43, 51
WDT....................................................................................43
Period..........................................................................51
Programming Considerations .....................................51
Time-out......................................................................43
X
XT..................................................................................39, 47
Z
Zero bit..................................................................................7
LIST OF EXAMPLES
Example 3-1: Instruction Pipeline Flow.............................. 10
Example 4-1: Indirect Addressing ...................................... 19
Example 4-2: How to Clear RAM Using Indirect
Addressing ................................................... 19
Example 5-1: Initializing PORTA........................................ 21
Example 5-2: Initializing PORTB........................................ 24
Example 5-3: Read-Modify-Write Instructions
on an I/O Port............................................... 25
Example 6-1: Changing Prescaler (Timer0
WDT) ........... 31
Example 6-2: Changing Prescaler (WDT
Timer0) ........... 31
Example 7-1: Data EEPROM Read ................................... 34
Example 7-2: Data EEPROM Write ................................... 34
Example 7-3: Write Verify .................................................. 35
Example 8-1: Saving STATUS and W Registers
in RAM ...................................................... 50
LIST OF FIGURES
Figure 3-1: PIC16F8X Block Diagram .............................. 8
Figure 3-2: Clock/Instruction Cycle ................................ 10
Figure 4-1: Program Memory Map and Stack -
PIC16F83/CR83........................................... 11
Figure 4-2: Program Memory Map and Stack -
PIC16F84/CR84........................................... 11
Figure 4-3: Register File Map - PIC16F83/CR83 ........... 13
Figure 4-4: Register File Map - PIC16F84/CR84 ........... 13
Figure 4-5: STATUS Register (Address 03h, 83h)......... 15
Figure 4-6: OPTION Register (Address 81h) ................. 16
Figure 4-7: INTCON Register (Address 0Bh, 8Bh) ........ 17
Figure 4-8: Loading of PC in Different Situations ........... 18
Figure 4-9: Direct/Indirect Addressing............................ 19
Figure 5-1: Block Diagram of Pins RA3:RA0.................. 21
Figure 5-2: Block Diagram of Pin RA4 ........................... 21
Figure 5-3: Block Diagram of Pins RB7:RB4.................. 23
Figure 5-4: Block Diagram of Pins RB3:RB0.................. 23
Figure 5-5: Successive I/O Operation ............................ 25
Figure 6-1: TMR0 Block Diagram................................... 27
Figure 6-2: TMR0 Timing: Internal Clock/
No Prescaler ................................................ 27
Figure 6-3: TMR0 Timing: Internal Clock/
Prescale 1:2 ................................................. 28
Figure 6-4: TMR0 Interrupt Timing ................................. 28
Figure 6-5: Timer0 Timing With External Clock.............. 29
Figure 6-6: Block Diagram of the TMR0/WDT
Prescaler...................................................... 30
Figure 7-1: EECON1 Register (Address 88h) ................ 33
Figure 8-1: Configuration Word - PIC16CR83
and PIC16CR84........................................... 38
Figure 8-2: Configuration Word - PIC16F83
and PIC16F84.............................................. 38
Figure 8-3: Crystal/Ceramic Resonator Operation
(HS, XT or LP OSC Configuration) .............. 39
Figure 8-4: External Clock Input Operation
(HS, XT or LP OSC Configuration) .............. 39
Figure 8-5: External Parallel Resonant Crystal
Oscillator Circuit........................................... 40
Figure 8-6: External Series Resonant Crystal
Oscillator Circuit........................................... 40
Figure 8-7: RC Oscillator Mode...................................... 41
Figure 8-8: Simplified Block Diagram of
On-Chip Reset Circuit .................................. 42
Figure 8-9: External Power-on Reset Circuit
(For Slow V
DD
Power-up)............................. 44
Figure 8-10: Time-out Sequence on Power-up
(MCLR
not Tied to V
DD
): Case 1.................. 45