 PIC microcontrollers in DIP and QFN packages PIC is a family of Harvard architecture microcontrollers made by Microchip Technology, derived from the PIC1650 originally developed by General Instrument's Microelectronics Division. Image File history File linksMetadata Download high-resolution version (1954x882, 522 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): PIC microcontroller User:Mikemurphy Metadata This file contains additional information, probably added from the digital camera or scanner...
Image File history File linksMetadata Download high-resolution version (1954x882, 522 KB) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): PIC microcontroller User:Mikemurphy Metadata This file contains additional information, probably added from the digital camera or scanner...
ICs in DIP14-Package Several PDIPs and CERDIPS. The large CERDIP in the foreground is an 8080 processor. ...
A QFN or Quad Flat package No leads is an integrated circuit package, used in surface mounted electronic circuits designs. ...
The term Harvard architecture originally referred to computer architectures that used physically separate storage and signal pathways for their instructions and data (in contrast to the von Neumann architecture). ...
It has been suggested that this article or section be merged with embedded microprocessor. ...
Microchip Technology (NASDAQ: MCHP) is a manufacturer of semiconductors, founded in ??. Its products include microcontrollers (PICmicro, dsPIC, PIC24), EEPROM and Flash memory devices, KEELOQ devices, radio frequency (RF) devices, battery management devices, interface devices, analog devices and many others. ...
General Instrument (GI) was a diversified electronics manufacturer which specialised in semiconductors and cable television equipment. ...
PICs are popular with developers and hobbyists alike due to their low cost, wide availability, large user base, extensive collection of application notes, availability of low cost or free development tools, and serial programming (and re-programming with flash memory) capability.
Microchip recently announced the shipment of its five billionth PIC processor.[1]
Core Architecture of the 8-bit CPUs
The PIC architecture is distinctively minimalist. It is characterised by the following features: - separate code and data spaces (Harvard architecture)
- a small number of fixed length instructions
- most instructions are single cycle execution (4 clock cycles), with single delay cycles upon branches and skips
- a single accumulator (W), the use of which (as source operand) is implied (ie is not encoded in the opcode)
- All RAM locations function as registers as both source and/or destination of math and other functions.[1]
- a hardware stack for storing return addresses
- a fairly small amount of addressable data space (typically 256 bytes), extended through banking
- data space mapped CPU, port, and peripheral registers
- the program counter is also mapped into the data space and writable (this is used to synthesize indirect jumps)
Unlike most other CPUs, there is no distinction between "memory" and "register" space because the RAM serves the job of both memory and registers, and the RAM is usually just referred to as the register file or simply as the registers. In a computer CPU, an accumulator is a register in which intermediate arithmetic and logic results are stored. ...
Data Space (RAM) PICs have a set of register files that function as general purpose ram, special purpose control registers for on-chip hardware resources are also mapped into the data space. The addressability of memory varies depending on device series, and all PIC devices have some banking mechanism to extend the addressing to additional memory. Later series of devices feature move instructions which can cover the whole addressable space, independent of the selected bank. In earlier devices (ie. the baseline and mid-range cores), any register move had to be through the accumulator.
To synthesize indirect addressing, a "file select register" (FSR) and "indirect register" (INDF) are used: A read or write to INDF will be to the memory pointed to by FSR. Later devices extended this concept with post and pre increment/decrement for greater efficiency in accessing sequentially stored data. This also allows FSR to be treated like a stack pointer.
External data memory is not directly addressable except in some high pin count PIC18 devices.
Code Space All PICs feature Harvard architecture, so the code space and the data space are separate. PIC code space is generally implemented as EPROM, ROM, or FLASH ROM. The term Harvard architecture originally referred to computer architectures that used physically separate storage and signal pathways for their instructions and data (in contrast to the von Neumann architecture). ...
In general, external code memory is not directly addressable due to the lack of an external memory interface. The exceptions are PIC17 and select high pin count PIC18 devices.
Word Size The word size of PICs can be a source of confusion. All PICs (except dsPICs and PIC24s) handle (and address) data in 8-bit chunks, so they should be called 8-bit microcontrollers. However, the unit of addressability of the code space is not generally the same as the data space. For example, PICs in the baseline and mid-range families have program memory addressable in the same wordsize as the instruction width, ie. 12 or 14 bits respectively. In contrast, in the PIC18 series, the program memory is addressed in 8-bit (bytes), which differs from the instruction width of 16 bits.
In order to be clear, the program memory capacity is usually stated in number of (single word) instructions, rather than in bytes.
Stacks PICs have a hardware call stack, which is used to save return addresses. The hardware stack is not software accessible on earlier devices, but this changed with the 18 series devices.
Hardware support for a general purpose parameter stack was lacking in early series, but this greatly improved in the 18 series, making the 18 series architecture more friendly to high level language compilers.
Instruction Set PICs instructions vary in number from about 35 instructions for the low-end PICs to about 70 instructions for the high-end PICs. The instruction set includes instructions to perform a variety of operations on registers directly, the accumulator and a literal constant or the accumulator and a register, as well as for conditional execution, and program branching. In a computer CPU, an accumulator is a register in which intermediate arithmetic and logic results are stored. ...
Some operations, such as bit setting and testing, can be performed on any register, but bi-operand arithmetic operations always involve W -- writing the result back to either W or the other operand register. To load a constant, it is necessary to load it into W before can be moved into another register. On the older cores, all register moves needed to pass through W, but this changed on the "high end" cores.
PIC cores have skip instructions which are used for conditional execution and branching. The skip instructions are: 'skip if bit set', and, 'skip if bit not set'. Because cores before PIC18 had only unconditional branch instructions, conditional jumps are synthesized by a conditional skip (with the opposite condition) followed by a branch. Skips are also of utility for conditional execution of any immediate single following instruction.
The PIC architecture has no (or very meager) hardware support for saving processor state when servicing interrupts. The 18 series improved this situation by implementing shadow registers which save several important registers during an interrupt.
Criticisms PIC microcontrollers have a very small set of instructions, leading some to consider them RISC devices. However, the PIC architecture does not reflect many of the advantages of RISC design. For example: This article does not cite any references or sources. ...
- PIC does not have a load-store architecture, as memory is directly referenced in arithmetic and logic operations
- it has a single working register, while RISC designs typically include 16 or more general purpose registers
- its addressing modes are not orthogonal, since some instructions can address RAM or immediate data, while others can only use the working register
- bank switching is required to access the entire RAM of many PIC devices, making the development of libraries of position-independent code complex and inefficient
- a stack cannot be implemented efficiently, so it is difficult to generate reentrant code
These properties have made it difficult to develop compilers that target PIC microcontrollers. While several commercial compilers are available, the Free software Small Device C Compiler has not yet completed support for PIC as of 2007. By contrast, Atmel's AVR microcontrollers—which are competitive with PIC in terms of hardware capabilities and price, but feature a RISC instruction set—have long been supported by the GNU C Compiler. Look up accumulator in Wiktionary, the free dictionary. ...
In computer architecture, a processor register is a small amount of very fast computer memory used to speed the execution of computer programs by providing quick access to commonly used values—typically, the values being in the midst of a calculation at a given point in time. ...
In mathematics, orthogonal is synonymous with perpendicular when used as a simple adjective that is not part of any longer phrase with a standard definition. ...
In mathematics and the mathematical sciences, a constant is a fixed, but possibly unspecified, value. ...
Bank switching (also known as paging, but only loosely related to the ordinary meaning of paging in computing) was a technique common in 8-bit microcomputer systems, to increase the amount of addressable RAM and ROM without extending the address bus. ...
In computing, position independent code (PIC) is object code that can execute at different locations in memory. ...
Simple representation of a stack In computer science, a stack is a temporary abstract data type and data structure based on the principle of Last In First Out (LIFO). ...
A computer program or routine is described as reentrant if it can be safely called recursively or from multiple processes. ...
Clockwise from top: The logo of the GNU Project (the GNU head), the Linux kernel mascot Tux the Penguin, and the FreeBSD daemon Free software is a term coined by Richard Stallman and the Free Software Foundation[1] to refer to software that can be used, studied, and modified without...
The Small Device C Compiler (SDCC) is a C compiler for several microcontollers. ...
2007 is a common year starting on Monday of the Gregorian calendar. ...
Atmel ATMEGA32 microcontroller Atmel AT90S2333 microcontroller Atmel Corporation (NASDAQ: ATML) is a manufacturer of semiconductors, founded in 1984. ...
The AVR is a Harvard architecture 8-bit RISC single chip microcontroller (µC) which was developed by Atmel in 1996. ...
The GNU Compiler Collection (usually shortened to GCC) is a set of programming language compilers produced by the GNU Project. ...
PIC assembly language code can be difficult to comprehend due to the limited addressing modes, code obfuscation via the "skip" instruction, and register juggling through the accumulator. Thankfully, the availability of high level language compilers has reduced the need for assembly language programming.
Other drawbacks have been addressed in the PIC18 series, but still apply to earlier cores:
- Data stored in program memory is space inefficient and/or time consuming to access, as it is not directly addressable. This is true of most Harvard architecture microcontrollers.
- The PIC architecture is somewhat unfriendly to high level language compilation.
- A data stack implementation (for parameters and locals) would be dreadfully inefficient, leading to compilers storing these values at fixed memory locations. Thus, most C compilers do not generate re-entrant code.
- The instruction set lacks an indexed addressing mode.
- The call stack is so small that program structure must often be flattened.
- The call stack is not addressable, so pre-emptive task switching cannot be implemented.
The term Harvard architecture originally referred to computer architectures that used physically separate storage and signal pathways for their instructions and data (in contrast to the von Neumann architecture). ...
Family Core Architectural Differences
Baseline Core Devices These devices feature a 12-bit wide code memory, and a tiny two level deep call stack. They are represented by PIC10 series, as well as some PIC12 and PIC16 devices. Baseline devices are available in 6-pin to 40-pin packages.
Mid-Range Core Devices These devices feature a 14-bit wide code memory, and an improved 8 level deep call stack. The instruction set differs very little from the baseline devices, but the increased opcode width allows more memory to be directly addressed. The mid-range core is available in the majority of devices labelled PIC12 and PIC16.
PIC17 High End Core Devices The 17 series never became popular and has been superseded by the PIC18 architecture. It is not recommended for new designs, and may be in limited availability.
Improvements over earlier cores are 16-bit wide opcodes (allowing many new instructions), and a 16 level deep call stack. PIC17 devices were produced in packages from 40 to 68 pins.
The 17 series introduced a number of important new features:
- a memory mapped accumulator
- read access to code memory (table reads)
- direct register to register moves (prior cores needed to move registers through the accumulator)
- an external program memory interface to expand the code space
- an 8bit x 8bit hardware multiplier
- a second indirect register pair
- auto-increment/decrement addressing controlled by control bits in a status register (ALUSTA)
PIC18 High End Core Devices Microchip introduced the PIC18 architecture in 2002 [2], and unlike the 17 series, it has proven to be very popular, with a large number of device variants presently in manufacture. In contrast to earlier devices, which were more often than not programmed in assembly, C has become the predominant development language.[citation needed]
The 18 series inherits most of the features and instructions of the 17 series, while adding a number of important new features:
- much deeper call stack (31 levels deep)
- the call stack may be read and written
- conditional branch instructions
- indexed addressing mode (PLUSW)
- extending the FSR registers to 12 bits, allowing them to linearly address the entire data address space
- the addition of another FSR register (bringing the number up to 3)
The auto increment/decrement feature was improved by removing the control bits and adding four new indirect registers per FSR. Depending on which indirect file regiser is being accessed it is possible to postdecrement, postincrement, or preincrement FSR; or form the effective address by adding W to FSR.
In more advanced PIC18 devices, an "extended mode" is available which makes the addressing even more favourable to compiled code:
- a new offset addressing mode; addresses which were relative to the access bank are now interpreted relative to the FSR2 register
- the addition of several new instructions, notable for manipulating the FSR registers.
All new PIC18 devices being sold today (July 2007) are extended devices, and many popular PIC18 devices that were not extended have been replaced with extended devices. For example, the recommended replacement for the 18F452 is the 18F4520.
These changes were primarily aimed at improving the efficiency of a data stack implementation. If FSR2 is used either as the stack pointer or frame pointer, stack items may be easily indexed -- allowing more efficient re-entrant code. Microchip C18 chooses to use FSR2 as a frame pointer.
PIC24 and dsPIC 16-bit Microcontrollers Microchip introduced the dsPIC series of chips in 2001 [3], and they entered mass production in late 2004. They are designed as general purpose microcontrollers with digital signal processing capabilities, and are Microchip's first inherently 16-bit microcontrollers. Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ...
Architecturally, although they share the PIC moniker, they are very different than the 8-bit PICs. The most notable differences are
- they feature a set of 16 working registers
- they fully support a stack in RAM, and do not have a hardware stack
Some features are: - hardware MAC (multiply-accumulate)
- barrel shifting
- bit reversal
- (16x16)-bit multiplication and other DSP operations.
- hardware support for loop indexing
dsPICs can be efficiently programmed in C using a variant of gcc. The multiply-accumulate operation computes a product and adds it to an accumulator. ...
A barrel shifter is a digital circuit that can shift a data word by any number of bits in a single cycle. ...
Digital signal processing (DSP) is the study of signals in a digital representation and the processing methods of these signals. ...
The GNU Compiler Collection (usually shortened to GCC) is a set of programming language compilers produced by the GNU Project. ...
Device Variants and Hardware Features PIC devices generally feature: - sleep mode (power savings)
- watchdog timer
- various crystal or RC oscillator configurations, or an external clock
Variants Within a series, there are still many device variants depending on what hardware resources the chip features. - general purpose i/o pins
- internal clock oscillators
- 8/16 Bit Timers
- Internal EEPROM Memory
- Synchronous/Asynchronous Serial Interface USART
- MSSP Peripheral for I²C and SPI Communications
- Capture/Compare and PWM modules
- Analog-to-digital converters
- USB, Ethernet, CAN interfacing support
- external memory interface
- Integrated analog RF front ends (PIC16F639, and rfPIC)
- KEELOQ Rolling code encryption peripheral (encode/decode)
An EEPROM (also called an E2PROM)[] or Electronically Erasable Programmable Read-Only Memory, is a non-volatile storage chip used in computers and other devices to store small amounts of volatile (configuration) data. ...
A UART or Universal Asynchronous Receiver-Transmitter is a piece of computer hardware that translates between parallel bits of data and serial bits. ...
I²C is a multi-master serial computer bus invented by Philips that is used to attach low-speed peripherals to a motherboard, embedded system, or cellphone. ...
The Serial Peripheral Interface Bus or SPI bus is a very loose standard for controlling almost any digital electronics that accepts a clocked serial stream of bits. ...
Pulse-width modulation of a signal or power source involves the modulation of its duty cycle, to either convey information over a communications channel or control the amount of power sent to a load. ...
4-channel stereo multiplexed analog-to-digital converter WM8775SEDS made by Wolfson Microelectronics placed on X-Fi Fatal1ty Pro sound card An analog-to-digital converter (abbreviated ADC, A/D or A to D) is an electronic integrated circuit (i/c) that converts continuous signals to discrete digital numbers. ...
A USB Series “A†plug, the most common USB plug Universal Serial Bus (USB) is a serial bus standard to interface devices. ...
Ethernet is a large, diverse family of frame-based computer networking technologies that operates at many speeds for local area networks (LANs). ...
Controller Area Network (CAN) is a broadcast, differential serial bus standard, originally developed in the 1980s by Robert Bosch GmbH, for connecting electronic control units (ECUs). ...
KeeLoq is a proprietary hardware-dedicated NLFSR-based block cipher. ...
Trends The old EPROM PICs are now gradually replaced by chips with Flash memory. Likewise, the original 12-bit instruction set of the PIC1650 and its direct descendants has been superseded by 14-bit and 16-bit instruction sets. Microchip still sells OTP (one-time-programmable) and windowed (UV-eraseable) versions of some of its EPROM based PICs for legacy support or volume orders. It should be noted that the Microchip website lists PICs that are not electrically erasable as OTP despite the fact that UV erasable windowed versions of these chips can be ordered. EPROM. The small quartz window admits UV light during erasure. ...
A USB flash drive. ...
EPROM. The small quartz window admits UV light during erasure. ...
Origins The original PIC was built to be used with GI's new 16-bit CPU, the CP1600. While generally a good CPU, the CP1600 had poor I/O performance, and the 8-bit PIC was developed in 1975 to improve performance of the overall system by offloading I/O tasks from the CPU. The PIC used simple microcode stored in ROM to perform its tasks, and although the term wasn't used at the time, it shares some common features with RISC designs. Die of an Intel 80486DX2 microprocessor (actual size: 12×6. ...
CPU can stand for: in computing: Central processing unit in journalism: Commonwealth Press Union in law enforcement: Crime prevention unit in software: Critical patch update, a type of software patch distributed by Oracle Corporation in Macleans College is often known as Ash Lim. ...
Energy Input: The energy placed into a reaction. ...
A microprogram is a program consisting of microcode that controls the different parts of a computers central processing unit (CPU). ...
Read-only memory (usually known by its acronym, ROM) is a class of storage media used in computers and other electronic devices. ...
This article does not cite any references or sources. ...
In 1985 General Instruments spun off their microelectronics division, and the new ownership cancelled almost everything — which by this time was mostly out-of-date. The PIC, however, was upgraded with EPROM to produce a programmable channel controller, and today a huge variety of PICs are available with various on-board peripherals (serial communication modules, UARTs, motor control kernels, etc.) and program memory from 512 words to 64k words and more (a "word" is one assembly language instruction, varying from 12, 14 or 16 bits depending on the specific PIC micro family). Year 1985 (MCMLXXXV) was a common year starting on Tuesday (link displays 1985 Gregorian calendar). ...
Microelectronics is a subfield of electronics. ...
EPROM. The small quartz window admits UV light during erasure. ...
A channel controller is a simple CPU used to handle the task of moving data to and from the memory of a computer. ...
In telecommunications and computer science, serial communications is the process of sending data one bit at one time, sequentially, over a communications channel or computer bus. ...
A UART or Universal Asynchronous Receiver-Transmitter is a piece of computer hardware that translates between parallel bits of data and serial bits. ...
This article is about the unit of information. ...
Look up micro- in Wiktionary, the free dictionary. ...
Microchip Technology does not use PIC as an acronym[citation needed]; in fact the brand name is PICmicro. It is generally regarded that PIC stands for Peripheral Interface Controller, although General Instruments' original acronym for the PIC1650 was "Programmable Intelligent Computer".[2]
 Various older (EPROM) PIC microcontrollers Image File history File linksMetadata Download high resolution version (1600x1200, 1025 KB) Summary Author Camillo Ferrari Olympus digital camera C-150 with macro-lens. ...
Image File history File linksMetadata Download high resolution version (1600x1200, 1025 KB) Summary Author Camillo Ferrari Olympus digital camera C-150 with macro-lens. ...
Development Tools and Languages
Commercially Supported Microchip provides a freeware IDE package called MPLAB, which includes an assembler, linker, software simulator, and debugger. They also sell C compilers for the PIC18 and dsPIC which integrate cleanly with MPLAB. Free student versions of the C compilers are also available, with some features disabled. The term Freeware refers to gratis proprietary software with closed source. ...
This article or section does not cite any references or sources. ...
A simulation is an imitation of some real device or state of affairs. ...
Several third parties make C, BASIC[3] and Pascal[4] language compilers for PICs, many of which integrate to MPLAB and/or feature their own IDE. C is a general-purpose, block structured, procedural, imperative computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system. ...
Screenshot of Atari BASIC, an early BASIC language for small computers. ...
Pascal is a structured imperative computer programming language, developed in 1970 by Niklaus Wirth as a language particularly suitable for structured programming. ...
A compiler is a computer program that translates a computer program written in one computer language (called the source language) into an equivalent program written in another computer language (called the output or the target language). ...
Open Source The following development tools are available for the PIC family under the GPL or other open sources licences. The GNU logo For other uses of GPL, see GPL (disambiguation). ...
GPUTILS is free and available from the GPUTILS website. GPUTILS is a GPL-licensed set of tools for the PIC microcontroller, comprising an assembler, disassembler, linker, and object file viewer. ...
GPUTILS is a GPL-licensed set of tools for the PIC microcontroller, comprising an assembler, disassembler, linker, and object file viewer. ...
GPSIM is an Open Source simulator for the PIC microcontrollers featuring hardware modules that simulate specific devices that might be connected to them, like LCDs. Reflective twisted nematic liquid crystal display. ...
SDCC supports 8 and 16-bit PIC micro controllers. Currently, throughout the SDCC website, the words, "Work is in progress", are frequently used to describe the status of SDCC's support for PICs. The Small Device C Compiler (SDCC) is a C compiler for several microcontollers. ...
Ktechlab is a free IDE for programming PIC Microcontroller. It allows one to write the program in C, Assembly, Microbe (a BASIC-like language) and using FlowChart Method. This article or section does not cite any references or sources. ...
C is a general-purpose, block structured, procedural, imperative computer programming language developed in 1972 by Dennis Ritchie at the Bell Telephone Laboratories for use with the Unix operating system. ...
See the terminology section, below, regarding inconsistent use of the terms assembly and assembler. ...
Screenshot of Atari BASIC, an early BASIC language for small computers. ...
Free software tools Free C, C++, Pascal, Basic compilers for the PIC microcontroller series.
PiKdev [4] runs on Linux and is a simple graphic IDE for the development of PIC-based applications. It currently supports assembly language. Non Open Source C language (Currently free 1/22/07) is also supported for PIC 18 devices. PiKdev is developed in C++ under Linux and is based on the KDE environment.
Piklab is a forked version of PiKdev and is managed as SourceForge Project. Piklab adds to Pikdev by providing support for programmers and debuggers. Currently, Piklab supports the ICD1, ICD2, PICkit1, PICKkit2, and PicStart+ as programming devices and has debugging support for ICD2 in addition to using the simulator, GPSim.[5] SourceForge is a collaborative revision control and software development management system. ...
Device Programmers
 A development board for low pin-count MCU, from Microchip Devices called "programmers" are traditionally used to get program code into the target PIC. Most PICs that Microchip currently sell feature ICSP (In Circuit Serial Programming) and/or LVP (Low Voltage Programming) capabilities, allowing the PIC to be programmed while it is sitting in the target circuit. ICSP programming is performed using two pins, clock and data, while a high voltage (12V) is present on the Vpp/MCLR pin. Low voltage programming dispenses with the high voltage, but reserves exclusive use of an I/O pin and can therefore be disabled to recover the pin for other uses (once disabled it can only be re-enabled using high voltage programming). Image File history File linksMetadata Download high resolution version (2288x1450, 418 KB) Description Description: The Microchip PICKit 1 (Flash Starter Kit) development board, for low-pin-count PIC microcontrollers. ...
Image File history File linksMetadata Download high resolution version (2288x1450, 418 KB) Description Description: The Microchip PICKit 1 (Flash Starter Kit) development board, for low-pin-count PIC microcontrollers. ...
In field of computer hardware, the term programmer refers to a hardware device that configures a programmable non-volatile circuits such as EEPROM or programmable logic circuits. ...
Look up circuit in Wiktionary, the free dictionary. ...
There are many programmers for PIC microcontrollers, ranging from the extremely simple designs which rely on ICSP to allow direct download of code from a host computer, to intelligent programmers that can verify the device at several supply voltages. Many of these complex programmers use a pre-programmed PIC themselves to send the programming commands to the PIC that is to be programmed. The intelligent type of programmer is needed to program earlier PIC models (mostly EPROM type) which do not support in-circuit programming.
Many of the higher end flash based PICs can also self-program (write to their own program memory). Demo boards are available with a small bootloader factory programmed that can be used to load user programs over an interface such as RS-232 or USB, thus obviating the need for a programmer device. Alternatively there is bootloader firmware available that the user can load onto the PIC using ICSP. The advantages of a bootloader over ICSP is the far superior programming speeds, immediate program execution following programming, and the ability to both debug and program using the same cable. RS-232 (also referred to as EIA RS-232C or V.24) is a standard for serial binary data interchange between a DTE (Data terminal equipment) and a DCE (Data communication equipment). ...
A USB Series “A†plug, the most common USB plug Universal Serial Bus (USB) is a serial bus standard to interface devices. ...
Microchip Programmers
 Microchip PICSTART Plus programmer There are many programmers/debuggers available directly from Microchip. Image File history File linksMetadata Size of this preview: 800 × 533 pixel Image in higher resolution (3456 × 2304 pixel, file size: 2. ...
Image File history File linksMetadata Size of this preview: 800 × 533 pixel Image in higher resolution (3456 × 2304 pixel, file size: 2. ...
Microchip Programmers (as of 10/2005)
- PICStart Plus (RS232 serial interface) : intelligent.
- Promate II (RS232 serial interface) : intelligent.
- MPLAB PM3 (RS232 serial and USB interface)
- ICD2 (RS232 serial and USB interface) : ICSP programming only (primary function is debugging).
- PICKit 1 (USB interface)
- PICKit 2 (USB interface)
Third-Party Programmers and Kits There are programmers available from other sources, ranging from plans as to how to build your own, to kits to put together yourself, to fully tested ready-to-go units. Some are simple designs which require a PC to do the low-level programming signalling (these typically connect to the serial or parallel port and consist of a few simple components), while others have the programming logic built into them (these typically use a serial or USB connection, are usually faster, and are many times built using PICs themselves for control). For a directory of PIC related tools and websites, see PIC microcontroller at the Open Directory Project . These are some common programmer types: A male DE-9 connector used for a serial port on a PC style computer. ...
It has been suggested that LPT, Centronics and IEEE 1284 be merged into this article or section. ...
The Open Directory Project (ODP), also known as dmoz (from , its original domain name), is a multilingual open content directory of World Wide Web links owned by Netscape that is constructed and maintained by a community of volunteer editors. ...
- Simple serial port ICSP programmers
- These generally rely on driving the PIC's Vss line negative to get the necessary voltage differences from programming. Hence they are compact and cheap but great care is needed if using them for in circuit programming.
- Simple parallel port ICSP programmers
- Simple to understand but often have much higher part counts and generally require external power supplies.
- Intelligent programmers
- Generally faster and more reliable (especially on laptops which tend to have idiosyncrasies in the way they implement their ports) but far more complex to build (in particular they tend to use a PIC in the programmer which must itself be programmed somehow).
Here are some ICSP programmers available: - home-made ICSP JDM Pic
- powerfull PIC PRESTO that supports ICSP, ISP, JTAG, I2C, SPI, Microwire interfaces, works on USB and comply with programming specifications
Major problem of home-made or very simple programmers is that these programmers do not comply with programming specifications and this can cause premature loss of data in the flash or EEPROM.
Also, in http://microspics.blogspot.com you will find a list of links to famous DIY programmers.
Debugging
Software Emulation MPLAB (which is a free download) includes a software emulator for PICs. However, software emulation of a microcontroller will always suffer from limited simulation of the devices interactions with its target circuit.
Proteus VSM is a commercial software product developed by Labcenter Electronics which allows simulation of many PICmicro devices along with a wide array of peripheral devices. This method can help bridge the gap between the limited peripheral support offered by the MPLAB simulator and traditional in-circuit debugging/emulating. The product interfaces directly with MPLAB to offer a schematic display of signals and peripheral devices.
In-Circuit Debugging Later model PICs feature an ICD (in-circuit debugging) interface, built into the CPU core. ICD debuggers (MPLAB ICD2 and other third party) can communicate with this interface using three lines. This cheap and simple debugging system comes at a price however, namely limited breakpoint count (1 on older pics 3 on newer PICs), loss of some IO (with the exception of some surface mount 44-pin PICs which have dedicated lines for debugging) and loss of some features of the chip. For small PICs, where the loss of IO caused by this method would be unacceptable, special headers are made which are fitted with PICs that have extra pins specifically for debugging.
In-Circuit Emulators Finally, microchip offers two full in circuit emulators: the MPLAB ICE2000 (parallel interface, a USB converter is available); and the newer MPLAB REAL ICE (USB connection). Both ICE tools can be used with the MPLAB IDE for full source-level debugging of code running on the target.
The ICE2000 requires emulator modules, and the test hardware must provide a socket which can take either an emulator module, or a production device.
The REAL ICE connects directly to production devices which support in-circuit emulation through the PGC/PGD programming interface, or through a high speed connection which uses two more pins. It supports the PIC24 and dsPIC families of processors.
The ICE4000 is no longer directly advertised on Microchip's website, and the purchasing page states that it is not recommended for new designs.
PIC clones Ubicom is a prominent supplier of software and communication processor platforms. ...
The Parallax SX line of microcontrollers were formally made by Ubicom. ...
Parallax, Inc. ...
OpenCores is a loose community of people who are interested in developing open source hardware (digital hardware) through electronic design automation, with a similar ethos to the free software movement. ...
Verilog is a hardware description language (HDL) used to model electronic systems. ...
8/16-bit PIC microcontroller product families These links take you to product selection matrices at the manufacturer's site.
8-bit Microcontrollers
16-bit Microcontrollers 16-bit Digital Signal Controllers The F in a name generally indicates the PICmicro uses flash memory and can be erased electronically. A C generally means it can only be erased by exposing the die to ultraviolet light (which is only possible if a windowed package style is used). An exception to this rule is the PIC16C84 which uses EEPROM and is therefore electrically erasable.
See also Wikibooks has more about this subject: Embedded Systems/PIC Microcontroller Image File history File links Wikibooks-logo-en. ...
The BASIC Stamp is a microcontroller with a small, specialized BASIC interpreter (PBASIC) built into ROM. It is made by Parallax, Inc. ...
The OOPic is an Object Oriented Programmable Integrated Circuit. ...
PICAXE is the name of a UK-sourced microcontroller system based on a range of Microchip PICs. ...
References - ^ Microchip Technology (2006-11-08). Microchip Technology Delivers Five Billionth PIC® Microcontroller. Press release. Retrieved on 2006-02-13.
- ^ "1977 Data Catalog", Micro Electronics from General Instrument Corporation http://www.rhoent.com/pic16xx.pdf
- ^ Oshon Software Project.
- ^ mikroElectronika Compilers.
- ^ Piklab Homepage (English). SourceForge.net (2007-02-01). Retrieved on 2007-02-10.
Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...
is the 312th day of the year (313th in leap years) in the Gregorian calendar. ...
A press release (sometimes known as a news release or press statement) is a written or recorded communication directed at members of the news media for the purpose of announcing something claimed as having news value. ...
Year 2006 (MMVI) was a common year starting on Sunday of the Gregorian calendar. ...
is the 44th day of the year in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...
is the 41st day of the year in the Gregorian calendar. ...
External links Wikimedia Commons has media related to: PIC microcontrollers - Microchip.com Official web site
- PIC Microcontroller Tutorial and Projects
- the PICList FAQ and Archive from the "PICList" email list hosted at MIT. A well respected source of manufacturer-independent solutions, source code, and expertise.
- GPUTILS Open Source assembler and linker.
- ae18 An Open Source verilog PIC18 core implementation.
- http://microspics.blogspot.com A list of DIY PIC programmers.
- Free software tools Free C, C++, Pascal, Basic compilers for the PIC microcontroller series.
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