Transcript Comparator Interrupt Flag bit

PIC
University of Belgrade
School of Electrical Engineering
Department of Computer Science
Authors:
Goran Timotic [email protected]
Gvozden Marinkovic [email protected]
Prof. Dr. Veljko Milutinovic [email protected]
PIC - Introduction

Microchip is the Embedded Control Solutions Company
 The company’s focus is on products that meet the needs of the
embedded control market
 Some of the benefits for the customer include:
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Quick time to market
Allows code changes to product, during production run
No Non-Recurring Engineering (NRE) charges for Mask Revisions
Ability to easily serialize the product
Ability to store calibration data, without additional hardware
Better able to maximize PICmicro MCU inventory
Less risk, since the same device is used for development as well as
for production.
2/60
PIC - Introduction

PICmicro devices are grouped by the size of
their Instruction Word
 The three current PICmicro families are:
– Base-Line: 12-bit Instruction Word length
– Mid-Range: 14-bit Instruction Word length
– High-End: 16-bit Instruction Word length
3/60
PIC - Introduction
PIC12 Family

PIC12C5XX Family - 8-Pin, 8-Bit CMOS Microcontrollers

PIC12CE5XX Family - 8-Pin, 8-Bit CMOS Microcontrollers with
EEPROM Data Memory

PIC12C67X Family - 8-Pin, 8-Bit CMOS Microcontrollers with A/D
Converter

PIC12CE67X Family - 8-Pin, 8-Bit CMOS Microcontrollers with A/D
Converter and EEPROM Data Memory
4/60
PIC - Introduction
PIC16 Family

PIC16C5X Family & PIC16HV540 - EPROM/ROM-Based 8-Bit CMOS
Microcontroller Series

PIC16C55X Family EPROM-Based 8-Bit CMOS Microcontrollers

PIC16C6X Family 8-Bit CMOS Microcontrollers
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PIC16X62X Family 18-Pin EPROM-Based 8-Bit CMOS Microcontrollers
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PIC16CE62X Family 8-Bit CMOS Microcontrollers with Analog
Comparators and EEPROM Data Memory

PIC16C7X Family 8-Bit CMOS Microcontrollers with A/D Converter

PIC16C7XX Family 8-Bit CMOS Microcontrollers with A/D Converter for
USB, PS/2 and Serial Device Applications

PIC16C9XX Family 8-Bit CMOS Microcontrollers with LCD Driver
5/60
PIC - Introduction
PIC17 Family

PIC17C4X Family - High-Performance 8-Bit CMOS EPROM/ROM
Microcontrollers

PIC17C7XX Family - High-Performance 8-Bit CMOS EPROM
Microcontrollers
6/60
PIC - Introduction

The high performance of the PICmicro™ devices can
be attributed to a number of architectural features
commonly found in RISC microprocessors:
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Harvard architecture
Long Word Instructions
Single Word Instructions
Single Cycle Instructions
Instruction Pipelining
Reduced Instruction Set
Register File Architecture
Orthogonal (Symmetric) Instructions
7/60
PIC - Architecture Overview
13
EPROM
Program
Memory
up to
8K x 14
8 Level Stack
(13-bit)
14
8
Data Bus
Program Counter
RAM
General
Purpose I/O
File Registers
up to
368 x 8
Program Bus
RAM Addr
Instruction reg
9
Addr MUX
7
Direct Addr
8
Indirect
Addr
FSR reg
8
STATUS reg
Instruction
Decode &
Control
Power-up Timer
3
MUX
Oscillator Start-up
Timer
Power-on Reset
Timing
Generation
Internal
RC clock
Watchdog Timer
Brown-out Reset
8
ALU
W reg
Peripheral Modules
8/60
PIC - Oscillator

The internal oscillator circuit is used to generate the device clock
 Four device clock periods generate one internal
instruction clock (TCY) cycle
 There are up to eight different modes,
which the oscillator may have:
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LP Low Frequency (Power) Crystal
XT Crystal/Resonator
HS High Speed Crystal/Resonator
RC External Resistor/Capacitor (same as EXTRC with CLKOUT)
EXTRC External Resistor/Capacitor
EXTRC External Resistor/Capacitor with CLKOUT
INTRC Internal 4 MHz Resistor/Capacitor
INTRC Internal 4 MHz Resistor/Capacitor with CLKOUT
9/60
PIC - Reset
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The reset logic is used to place the device into a known state
The source of the reset can be determined
by using the device status bits
Most registers are unaffected by a reset, their status is unknown
on POR and unchanged by all other resets
The other registers are forced to a “reset state” on Power-on
Reset, MCLR, WDT reset, Brown-out Reset, Parity Error Reset,
and on MCLR reset during SLEEP
While the PICmicro™ is in a reset state, the internal phase clock
is held at Q1 (beginning of an instruction cycle)
10/60
PIC - Reset 2

Devices differentiate between various kinds of reset:
– Power-on Reset (POR) - pulse is generated on-chip when
VDD rise is detected
– MCLR reset during normal operation
– MCLR reset during SLEEP
– WDT reset during normal operation
– Brown-out Reset (BOR) - places the device into reset when
the device voltage falls below a trip point (BVDD)
– Parity Error Reset (PER)
11/60
PIC - Instruction Flow/Pipelining
An “Instruction Cycle” consists of four Q cycles
(Q1, Q2, Q3, and Q4)
 Fetch takes one instruction cycle while decode
and execute takes another instruction cycle
 Due to Pipelining, each instruction effectively
executes in one cycle
 If an instruction causes the program counter to change (e.g. GOTO)
then an extra cycle is required to complete the instruction

12/60
PIC - Instruction Pipeline Flow
1. MOVLW 55h
TCY0
TCY1
Fetch 1
Execute 1
2. MOVWF PORTB
Fetch 2
3. CALL SUB_1
4. BSF PORTA, BIT3 (Forced NOP)
5. Instruction @ address SUB_1
TCY2
TCY3
TCY4
TCY5
Execute 2
Fetch 3
Execute 3
Fetch 4
Flush
Fetch SUB_1 Execute SUB_1
Fetch SUB_1+1
13/60
PIC - Central Processing Unit (CPU)

CPU is responsible for:
– fetching the correct instruction for execution
– decoding that instruction
– executing that instruction

Sometimes works in conjunction with the ALU to complete the
execution of the instruction (in arithmetic and logical operations)
 The CPU controls the program memory address bus, the data
memory address bus, and accesses to the stack
14/60
PIC - Instruction Clock

Each instruction cycle (TCY) is comprised of four Q cycles (Q1-Q4)
 The Q cycles provide the timing/designation for the Decode, Read,
Process Data, Write, etc., of each instruction cycle
 The four Q cycles that make up an instruction cycle (TCY)
can be generalized as:
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Q1: Instruction Decode Cycle or forced No operation
Q2: Instruction Read Data Cycle or No operation
Q3: Process the Data
Q4: Instruction Write Data Cycle or No operation
15/60
PIC - Arithmetic Logical Unit (ALU)

PICmicro MCUs contain an 8-bit ALU and an 8-bit working register
 The ALU is a general purpose arithmetic and logical unit
 ALU performs arithmetic and Boolean functions between
the data in the working register and any register file
 The ALU is 8-bits wide and is capable of addition,
subtraction, shift and logical operations
– In two-operand instructions
• one operand is the working register (W register)
• the other operand is a file register or an immediate constant
– In single operand instructions,
• the operand is either the W register or a file register
16/60
PIC - STATUS Register

The STATUS register contains the arithmetic status of the ALU, the
RESET status and the bank select bits for data memory
IRP
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RP1
RP0
TO
PD
Z
DC
C
IRP: Register Bank Select bit (used for indirect addressing)
RP1:RP0: Register Bank Select bits (used for direct addressing)
TO: Time-out bit
PD: Power-down bit
Z: Zero bit
DC: Digit carry/borrow bit
C: Carry/borrow bit
17/60
PIC - OPTION_REG Register

Readable and writable register which contains various control
bits to configure the TMR0/WDT prescaler, the external INT
Interrupt, TMR0, and the weak pull-ups on PORTB
RBPU
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INTEDG
T0CS
T0SE
PSA
PS2
PS1
PS0
RBPU: PORTB Pull-up Enable bit
INTEDG: Interrupt Edge Select bit
T0CS: TMR0 Clock Source Select bit
T0SE: TMR0 Source Edge Select bit
PSA: Prescaler Assignment bit
PS2:PS0: Prescaler Rate Select bits
18/60
PIC - PCON Register

The Power Control (PCON) register contains flag bit(s),
that together with the TO and PD bits, allows the user to
differentiate between the device resets
MPEEN
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PER
POR
BOR
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MPEEN: Memory Parity Error Circuitry Status bit
 PER: Memory Parity Error Reset Status bit
 POR: Power-on Reset Status bit
 BOR: Brown-out Reset Status bit
19/60
PIC - Memory Organization

There are two memory blocks
– Program memory
– Data memory
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Each block has its own bus, so that access to each block
can occur during the same oscillator cycle
 The data memory can further be broken down into General
Purpose RAM and the Special Func-tion Registers (SFRs)
20/60
PIC - Program Memory Organization
PCLATH
PC<12:8>
PCL
13
Stack Level 1
Stack Level 8
2K
Reset Vector
0000h
Interrupt Vector
0004h
0005h
4K
6K
On-chip Program
Memory (Page 0)
8K
On-chip Program
Memory (Page 1)
On-chip Program
Memory (Page 2)
On-chip Program
Memory (Page 3)
07FFh
0800h
0FFFh
1000h
17FFh
1800h
1FFFh
21/60
PIC - Program Memory Organization
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Mid-Range MCU devices have a 13-bit program counter capable of
addressing an 8K x 14 program memory space
The width of the program memory bus (instruction word) is 14-bits
Since all instructions are a single word, a device with an 8K x 14
program memory has space for 8K of instructions
This program memory space is divided
into four pages of 2K words each
To jump between the program memory pages, the high bits
of the Program Counter (PC) must be modified.
This is done by writing the desired value into a SFR called
PCLATH (ProgramCounter Latch High)
22/60
PIC - Program Memory Organization

Reset Vector - on any device, a reset forces
the Program Counter (PC) to address 0h
 Interrupt Vector - when an interrupt is acknowledged
the PC is forced to address 0004h
 Calibration Information - some devices have calibration
information stored in their program memory.
This information is programmed by Microchip when the
device is under final test
 Computed GOTO - accomplished by adding an offset
to the program counter (ADDWF PCL)
23/60
PIC - Program Memory Organization

Program Counter (PC) - specifies the address of the instruction to
fetch for execution
– The low byte is called the PCL register.
This
register is readable and writable
– The high byte is called the PCH register. This register contains the
PC<12:8> bits and is not directly readable or writable. All updates to
the PCH register go through the PCLATH register

Stack - 8-level deep x 13-bit wide hardware stack
– allows a combination of up to 8 program calls and interrupts to occur
– contains the return address from this branch in program execution
24/60
PIC - Program Memory Organization
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Program Memory Paging
25/60
PIC - Data Memory Organization

Data memory is made up of the Special Function Registers (SFR)
area, and the General Purpose Registers (GPR) area
 General Purpose Registers (GPR)
– GPRs are the general area for data storage and scratch pad operations
– We refer to this area as the Common RAM

Special Function Registers (SFR)
– The SFRs are used by the CPU and Peripheral Modules for controlling
the desired operation of the device.
– These registers are implemented as static RAM
26/60
PIC - Data EEPROM
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The EEPROM data memory is readable and writable
during normal operation (full VDD range)
A byte write automatically erases the location
and writes the new data (erase before write)
This memory is not directly mapped in the register file space
It is indirectly addressed through the Special Function Registers
There are four SFRs used to read and write this memory
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EECON1
EECON2 (not a physically implemented register)
EEDATA - holds the 8-bit data for read/write
EEADR - holds the address of the EEPROM location being accessed
27/60
PIC - Interrupts

One interrupt source for each peripheral module
 Some modules may generate multiple interrupts
(such as the USART module)
 There is a minimum of one register used in the control
and status of the interrupts (INTCON)
 If the device has peripheral interrupts, then it will have registers to
enable the peripheral interrupts and registers to hold the interrupt
flag bits. Depending on the device, the registers are:
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PIE1
PIR1
PIE2
PIR2
28/60
PIC - Interrupts
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The current interrupts are:
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INT Pin Interrupt (external interrupt)
TMR0 Overflow Interrupt
PORTB Change Interrupt (pins RB7:RB4)
Comparator Change Interrupt
Parallel Slave Port Interrupt
USART Interrupts
Receive Interrupt
Transmit Interrupt
A/D Conversion Complete Interrupt
LCD Interrupt.
Data EEPROM Write Complete Interrupt
Timer1 Overflow Interrupt
Timer2 Overflow Interrupt
CCP Interrupt
SSP Interrupt
29/60
PIC - Interrupts

Control Registers
– INTCON Register
– PIE Register(s)
– PIR Register(s)
30/60
PIC - Interrupts

INTCON Register - readable and writable register,
which contains various enable and flag bits
GIE
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PEIE
T0IE
INTE
RBIE
T0IF
INTF
RBIF
GIE: Global Interrupt Enable bit
PEIE: Peripheral Interrupt Enable bit
T0IE: TMR0 Overflow Interrupt Enable bit
INTE: INT External Interrupt Enable bit
RBIE: RB Port Change Interrupt Enable bit
T0IF: TMR0 Overflow Interrupt Flag bit
INTF: INT External Interrupt Flag bit
RBIF: RB Port Change Interrupt Flag bit
31/60
PIC - Interrupts
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PIE Register(s) - Peripheral Interrupt Enable register(s)
(the number of PIE registers depends on the number
of peripheral interrupt sources)
The bit position of the enable bits is device dependent
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TMR1IE: TMR1 Overflow Interrupt Enable bit
TMR2IE: TMR2 to PR2 Match Interrupt Enable bit
CCP1IE: CCP1 Interrupt Enable bit
CCP2IE: CCP2 Interrupt Enable bit
SSPIE: Synchronous Serial Port Interrupt Enable bit
32/60
PIC - Interrupts
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RCIE: USART Receive Interrupt Enable bit
TXIE: USART Transmit Interrupt Enable bit
ADIE: A/D Converter Interrupt Enable bit
ADCIE: Slope A/D Converter comparator Trip Interrupt Enable bit
OVFIE: Slope A/D TMR Overflow Interrupt Enable bit
PSPIE: Parallel Slave Port Read/Write Interrupt Enable bit
EEIE: EE Write Complete Interrupt Enable bit
LCDIE: LCD Interrupt Enable bit
CMIE: Comparator Interrupt Enable bit
33/60
PIC - Interrupts

PIR Register(s) - Peripheral Interrupt Flag registers contain the
individual flag bits for the peripheral interrupts
The bit position of the enable bits is device dependent
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TMR1IF: TMR1 Overflow Interrupt Flag bit
TMR2IF: TMR2 to PR2 Match Interrupt Flag bit
CCP1IF: CCP1 Interrupt Flag bit
CCP2IF: CCP2 Interrupt Flag bit
SSPIF: Synchronous Serial Port Interrupt Flag bit
RCIF: USART Receive Interrupt Flag bit
TXIF: USART Transmit Interrupt Flag bit
34/60
PIC - Interrupts
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ADIF: A/D Converter Interrupt Flag bit
ADCIF: Slope A/D Converter Comparator Trip Interrupt Flag bit
OVFIF: Slope A/D TMR Overflow Interrupt Flag bit
PSPIF: Parallel Slave Port Read/Write Interrupt Flag bit
EEIF: EE Write Complete Interrupt Flag bit
LCDIF: LCD Interrupt Flag bit
CMIF: Comparator Interrupt Flag bit
35/60
PIC - Interrupts

Interrupt Latency
– Interrupt latency is defined as the time from the interrupt event (the
interrupt flag bit gets set) to the time that the instruction at address
0004h starts execution (when that interrupt is enabled)
– For synchronous interrupts (typically internal), the latency is 3TCY
– For asynchronous interrupts (typically external), the interrupt latency
will be 3 - 3.75TCY
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Context Saving During Interrupts
– During an interrupt, only the return PC value is saved on the stack
– Typically, users may wish to save key registers during an interrupt e.g.
W register and STATUS register.
This has to be implemented in software
36/60
PIC - I/O

General purpose I/O pins can be considered
the simplest of peripherals
 They allow the PICmicro™ to monitor and control other devices
 To add flexibility and functionality to a device, some pins are
multiplexed with an alternate function(s)
37/60
PIC - I/O Descriptions
Pin Name
AN0..AN15
AVDD
AVSS
C1, C2
CCP1, CCP2
CDAC
CK
CLKIN
CLKOUT
CMPA, CMPB
COM0..COM3
CS
DT
GP0..GP5
INT
MCLR/VPP
NC
Description
Analog Input
Analog Power
Analog Ground
LCD Voltage Generation
Capture1(2) input/Compare1(2) output/PWM1(2) output
A/D ramp current source output
USART Synchronous Clock
External clock source input
Oscillator crystal output.
Comparator A (B) output
LCD Common Driver0 (1, 2, 3)
Chip select control for parallel slave port
USART Synchronous Data
GP is a bi-directional I/O port
External Interrupt
Master clear (reset) input or programming voltage input
These pins should be left unconnected
38/60
PIC - I/O Descriptions
Pin Name
OSC1
OSC2
PBTN
PSP0..PSP7
RA0..RA5
RB0..RB7
RC0..RC7
RD
RD0..RD7
RE0..RE7
REFA, REFB
RF0..RF7
RG0..RG7
RX
SCL
SCLA, SCLB
SDA
Description
Oscillator crystal input or external clock source input
Oscillator crystal output
Input with weak pull-up resistor
Parallel Slave Port for interfacing to a microprocessor port
PORTA is a bi-directional I/O port
PORTB is a bi-directional I/O port
PORTC is a bi-directional I/O port
Read control for parallel slave port
PORTD is a bi-directional I/O port
PORTE is a bi-directional I/O port
Programmable reference A (B) output
PORTF is a digital input or LCD Segment Driver Port
PORTG is a digital input or LCD Segment Driver Port
USART Asynchronous Receive
Synchronous serial clock input/output for I 2C mode.
Synchronous serial clock for I2C interface.
I2C ™ Data I/O
39/60
PIC - I/O Descriptions
Pin Name
SDAA, SDAB
SCK
SDI
SDO
SS
SEG00..SEG31
SUM
T0CKI
T1CKI
T1OSO
T1OSI
TX
VLCD1...VLCD3
VLCDADJ
VREF
VREG
VSS
VDD
WR
Description
Synchronous serial data I/O for I 2 C interface
Synchronous serial clock input/output for SPI mode
SPI Data In
SPI Data Out (SPI mode)
SPI Slave Select input
LCD Segment Driver00 through Driver31
AN1 summing junction output
Timer0 external clock input
Timer1 external clock input
Timer1 oscillator output
Timer1 oscillator input
USART Asynchronous Transmit
LCD Voltage
LCD Voltage Generation
Analog High Voltage Reference input.
Output to control the gate of an external N-FET for voltage regulation
Ground reference for logic and I/O pins
Positive supply for logic and I/O pins
Write control for parallel slave port
40/60
PIC - Parallel Slave Port (PSP)

Some devices have an 8-bit wide Parallel Slave Port (PSP)
 This port is multiplexed onto one of the devices I/O ports
 The PORT operates as an 8-bit wide Parallel Slave Port, or
microprocessor port, when the PSPMODE control bit is set
(in this mode, the input buffers are TTL)
41/60
PIC - Timer0

The Timer0 module has the following features:
–
–
–
–
–
–
8-bit timer/counter
Readable and writable
8-bit software programmable prescaler
Clock source selectable to be external or internal
Interrupt on overflow from FFh to 00h
Edge select for external clock
42/60
PIC - Timer1

The Timer1 module is a 16-bit timer/counter
 It consists of two 8-bit registers (TMR1H and TMR1L),
which are readable and writable
 Timer1 can operate in one of three modes:
– As a synchronous timer
– As a synchronous counter
– As an asynchronous counter
43/60
PIC - Timer2

Timer2 is an 8-bit timer with
– Prescaler
– Postscaler
– Period register

Using the prescaler and postscaler at their maximum settings,
the overflow time is the same as a 16-bit timer
44/60
PIC - Capture/Compare/PWM

Each CCP (Capture/Compare/PWM) module contains a 16-bit
register which can operate in three modes:
– As a 16-bit capture register
– As a 16-bit compare register
– As a 10-bit PWM master/slave Duty Cycle register

The CCP modules are identical in operation,
with the exception of the operation of the special event
trigger
45/60
PIC - Synchronous Serial Port (SSP)

The Synchronous Serial Port (SSP) module is a
serial interface useful for communicating with other
peripherals or microcontroller devices
 These peripheral devices may be serial EEPROMs,
shift registers, display drivers, A/D converters, etc.
 The SSP module can operate in one of two modes:
– Serial Peripheral Interface (SPI™)
– Inter-Integrated Circuit (I2C™)
• Slave mode
• I/O slope control, and Start and Stop bit detection to ease software
implementation of Master and Multi-master modes
46/60
PIC - Synchronous Serial Port (SSP)

Serial Peripheral Interface (SPI™)
– Allows 8-bits of data to be synchronously transmitted
and received simultaneously
– All four modes of SPI are supported, as well as Microwire™
(sample edge) when the SPI is in the master mode
– To accomplish communication, typically three pins are used:
• Serial Data Out (SDO)
• Serial Data In (SDI)
• Serial Clock (SCK)
47/60
PIC - Synchronous Serial Port (SSP)

Inter-Integrated Circuit (I2C™)
– The SSP module in I2C mode fully implements all slave functions,
except general call support
– Provides interrupts on start and stop bits in hardware to facilitate
software implementations of the master functions
– Implements the standard mode specifications
as well as 7-bit and 10-bit addressing
48/60
PIC - USART

The Universal Synchronous Asynchronous Receiver Transmitter
(USART) module is one of the two serial I/O modules
(other is the SSP module)
 The USART can be configured in the following modes:
– Asynchronous (full duplex)
• CRT terminals
• personal computers
– Synchronous - Master (half duplex)
• A/D or D/A integrated circuits
• Serial EEPROMs etc.
– Synchronous - Slave (half duplex)
49/60
PIC - A/D Converter

The A/D allows conversion of an analog input signal
to a corresponding 8-bit digital number
 The output of the sample and hold is the input into the converter,
which generates the result via successive approximation
 The A/D converter has a unique feature of being able to operate
while the device is in SLEEP mode
 The A/D module has three registers:
– A/D Result Register (ADRES)
– A/D Control Register0 (ADCON0) - controls the operation
of the A/D module
– A/D Control Register1 (ADCON1) - configures the functions
of the port pins
50/60
PIC - LCD

The LCD module generates the timing control to drive a static or
multiplexed LCD panel, with support for up to 32 segments
multiplexed with up to four commons
 The interface to the module consists of three control registers
used to define the timing requirements of the LCD panel
– LCDCON
– LCDSE
– LCDPS

Up to 16 LCD data registers (LCD00-LCD15) that represent the
array of the pixel data
51/60
PIC - Watch Dog Timer (WDT)
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The Watchdog Timer (WDT) is a free running on-chip RC oscillator
which does not require any external components
The Watchdog Timer (WDT) is enabled/disabled by a device
configuration bit. If the WDT is enabled, software execution
may not disable this function
During normal operation, a WDT time-out generates a device RESET
If the device is in SLEEP mode, a WDT time-out causes the device
to wake-up and continue with normal operation, this is known as a
WDT wake-up
The WDT can be permanently disabled by clearing the WDTE configuration bit
52/60
PIC - Device Configuration Bits

The device configuration bits allow each user to customize certain
aspects of the device to the needs of the application
 When the device powers up, the state of these bits determines the
modes that the device uses
 These bits are mapped in program memory location 2007h
 This location is not accessible during normal device operation
(can be accessed only during programming mode)
53/60
PIC - Voltage Reference

The Voltage Reference is a 16-tap resistor ladder network that
provides a selectable voltage reference
 The resistor ladder is segmented to provide two ranges of VREF
values and has a power-down function to conserve power when
the reference is not being used
54/60
PIC - Clock/Instruction Cycle

The clock input (from OSC1) is internally divided by four to
generate four non-overlapping quadrature clocks, namely Q1, Q2,
Q3, and Q4
 Internally, the program counter (PC) is incremented every Q1, and
the instruction is fetched from the program memory and latched
into the instruction register in Q4
 The instruction is decoded and executed during the following Q1
through Q4
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PIC - Clock/Instruction Cycle
TCY1
Q1
Q2
Q3
TCY2
Q4
Q1
Q2
Q3
TCY3
Q4
Q1
Q2
Q3
Q4
OSC1
Q1
Q2
Q3
Q4
PC
OSC2/CLKOUT
Fetch INST (PC)
Execute INST (PC-1)
Fetch INST (PC+1)
Execute INST (PC)
Fetch INST (PC+2)
Execute INST (PC+1)
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PIC - Instruction Format
Byte-oriented file register operations
13
8
OPCODE
7
6
0
d
f (FILE #)
Bit-oriented file register operations
13
10 9
OPCODE
7 6
b (BIT #)
0
f (FILE #)
Literal and control operations - General
13
7 6
OPCODE
0
k (literal)
Literal and control operations - CALL and GOTO instructions only
13
10 9
OPCODE
0
k (literal)
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PIC - Instruction Set
BYTE-ORIENTED FILE REGISTER OPERATIONS
ADDWF
f, d Add W and f
ANDWF
f, d AND W with f
CLRF
f Clear f
CLRW
- Clear W
COMF
f, d Complement f
DECF
f, d Decrement f
DECFSZ
f, d Decrement f, Skip if 0
INCF
f, d Increment f
INCFSZ
f, d Increment f, Skip if 0
IORWF
f, d Inclusive OR W with f
MOVF
f, d Move f
MOVWF
f Move W to f
NOP
- No Operation
RLF
f, d Rotate Left f through Carry
RRF
f, d Rotate Right f through Carry
SUBWF
f, d Subtract W from f
SWAPF
f, d Swap nibbles in f
XORWF
f, d Exclusive OR W with f
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PIC - Instruction Set
BIT-ORIENTED FILE REGISTER OPERATIONS
BCF
f, b Bit Clear f
BSF
f, b Bit Set f
BTFSC
f, b Bit Test f, Skip if Clear
BTFSS
f, b Bit Test f, Skip if Set
LITERAL AND CONTROL OPERATIONS
ADDLW
k Add literal and W
ANDLW
k AND literal with W
CALL
k Call subroutine
CLRWDT
- Clear Watchdog Timer
GOTO
k Go to address
IORLW
k Inclusive OR literal with W
MOVLW
k Move literal to W
RETFIE
- Return from interrupt
RETLW
k Return with literal in W
RETURN
- Return from Subroutine
SLEEP
- Go into standby mode
SUBLW
k Subtract W from literal
XORLW
k Exclusive OR literal with W
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PIC - ICSP™
ICSP™ is a short for In-Circuit Serial Programming™
 In-Circuit Serial Programming is a great way to reduce inventory
overhead and time-to-market for product
 All midrange devices can be ICSP™ while in the end application
circuit
 This is simply done with two lines for clock and data, and three
other lines for power, ground, and the programming voltage

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