PIC17C4X
WDT ........................................................................... 99, 103
Clearing the WDT .................................................... 103
Normal Timer ........................................................... 103
Period ....................................................................... 103
Programming Considerations .................................. 103
WDTPS0 ............................................................................ 99
WDTPS1 ............................................................................ 99
WREG ................................................................................ 34
LIST OF EXAMPLES
Example 3-1: Signed Math ..................................................9
Example 3-2: Instruction Pipeline Flow .............................14
Example 5-1: Saving STATUS and WREG in RAM ..........27
Example 6-1: Indirect Addressing......................................40
Example 7-1: Table Write..................................................46
Example 7-2: Table Read..................................................48
Example 8-1: 8 x 8 Multiply Routine..................................49
Example 8-2: 8 x 8 Signed Multiply Routine......................49
Example 8-3: 16 x 16 Multiply Routine..............................50
Example 8-4: 16 x 16 Signed Multiply Routine..................51
Example 9-1: Initializing PORTB .......................................57
Example 9-2: Initializing PORTC.......................................58
Example 9-3: Initializing PORTD.......................................60
Example 9-4: Initializing PORTE .......................................62
Example 9-5: Read Modify Write Instructions on an
X
XORLW ............................................................................ 141
XORWF ............................................................................ 141
Z
I/O Port........................................................64
Z ..................................................................................... 9, 36
Zero (Z) ................................................................................ 9
Example 11-1: 16-Bit Read .................................................69
Example 11-2: 16-Bit Write..................................................69
Example 12-1: Sequence to Read Capture Registers.........78
Example 12-2: Writing to TMR3 ..........................................80
Example 12-3: Reading from TMR3....................................80
Example 13-1: Calculating Baud Rate Error........................86
Example F-1: PIC17C42 to Sleep....................................223
LIST OF FIGURES
Figure 3-1:
Figure 3-2:
PIC17C42 Block Diagram ...........................10
PIC17CR42/42A/43/R43/44 Block
Diagram.......................................................11
Clock/Instruction Cycle................................14
Simplified Block Diagram of On-chip
Figure 3-3:
Figure 4-1:
Reset Circuit................................................15
Time-Out Sequence on Power-Up
(MCLR Tied to VDD) ....................................17
Time-Out Sequence on Power-Up
Figure 4-2:
Figure 4-3:
(MCLR NOT Tied to VDD)............................17
Slow Rise Time (MCLR Tied to VDD) ..........17
Oscillator Start-Up Time..............................18
Using On-Chip POR....................................18
Brown-out Protection Circuit 1.....................18
PIC17C42 External Power-On Reset
Figure 4-4:
Figure 4-5:
Figure 4-6:
Figure 4-7:
Figure 4-8:
Circuit (For Slow VDD Power-Up)................18
Brown-out Protection Circuit 2.....................18
Interrupt Logic .............................................21
INTSTA Register (Address: 07h,
Figure 4-9:
Figure 5-1:
Figure 5-2:
Unbanked)...................................................22
PIE Register (Address: 17h, Bank 1) ..........23
PIR Register (Address: 16h, Bank 1) ..........24
INT Pin / T0CKI Pin Interrupt Timing...........26
Program Memory Map and Stack................29
Memory Map in Different Modes .................30
External Program Memory Access
Figure 5-3:
Figure 5-4:
Figure 5-5:
Figure 6-1:
Figure 6-2:
Figure 6-3:
Waveforms ..................................................31
Typical External Program Memory
Figure 6-4:
Connection Diagram....................................31
PIC17C42 Register File Map.......................33
PIC17CR42/42A/43/R43/44 Register
Figure 6-5:
Figure 6-6:
File Map.......................................................33
ALUSTA Register (Address: 04h,
Unbanked)...................................................36
CPUSTA Register (Address: 06h,
Unbanked)...................................................37
T0STA Register (Address: 05h,
Figure 6-7:
Figure 6-8:
Figure 6-9:
Unbanked)...................................................38
Figure 6-10: Indirect Addressing......................................39
Figure 6-11: Program Counter Operation........................41
1996 Microchip Technology Inc.
DS30412C-page 231
MICROCHIP [ MICROCHIP ]
