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| - | A microcontroller (or MCU, short for microcontroller unit) is a small computer (SoC) on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of Ferroelectric RAM, NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used in personal computers or other general purpose applications consisting of various discrete chips. | + | A microcontroller (or [[http://www.eeboard.com|MCU]], short for microcontroller unit) is a small computer (SoC) on a single integrated circuit containing a processor core, memory, and programmable input/output peripherals. Program memory in the form of Ferroelectric RAM, NOR flash or OTP ROM is also often included on chip, as well as a typically small amount of RAM. Microcontrollers are designed for embedded applications, in contrast to the microprocessors used in personal computers or other general purpose applications consisting of various discrete chips. |
| Microcontrollers are used in automatically controlled products and devices, such as automobile engine control systems, implantable medical devices, remote controls, office machines, appliances, power tools, toys and other embedded systems. By reducing the size and cost compared to a design that uses a separate microprocessor, memory, and input/output devices, microcontrollers make it economical to digitally control even more devices and processes. Mixed signal microcontrollers are common, integrating analog components needed to control non-digital electronic systems. | Microcontrollers are used in automatically controlled products and devices, such as automobile engine control systems, implantable medical devices, remote controls, office machines, appliances, power tools, toys and other embedded systems. By reducing the size and cost compared to a design that uses a separate microprocessor, memory, and input/output devices, microcontrollers make it economical to digitally control even more devices and processes. Mixed signal microcontrollers are common, integrating analog components needed to control non-digital electronic systems. | ||
| Some microcontrollers may use four-bit words and operate at clock rate frequencies as low as 4 kHz, for low power consumption (single-digit milliwatts or microwatts). They will generally have the ability to retain functionality while waiting for an event such as a button press or other interrupt; power consumption while sleeping (CPU clock and most peripherals off) may be just nanowatts, making many of them well suited for long lasting battery applications. Other microcontrollers may serve performance-critical roles, where they may need to act more like a digital signal processor (DSP), with higher clock speeds and power consumption. | Some microcontrollers may use four-bit words and operate at clock rate frequencies as low as 4 kHz, for low power consumption (single-digit milliwatts or microwatts). They will generally have the ability to retain functionality while waiting for an event such as a button press or other interrupt; power consumption while sleeping (CPU clock and most peripherals off) may be just nanowatts, making many of them well suited for long lasting battery applications. Other microcontrollers may serve performance-critical roles, where they may need to act more like a digital signal processor (DSP), with higher clock speeds and power consumption. | ||
| - | History[edit] | + | |
| + | ====History==== | ||
| The first microprocessor was the 4-bit Intel 4004 released in 1971, with the Intel 8008 and other more capable microprocessors becoming available over the next several years. However, both processors required external chips to implement a working system, raising total system cost, and making it impossible to economically computerize appliances. | The first microprocessor was the 4-bit Intel 4004 released in 1971, with the Intel 8008 and other more capable microprocessors becoming available over the next several years. However, both processors required external chips to implement a working system, raising total system cost, and making it impossible to economically computerize appliances. | ||
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| In the future, MRAM could potentially be used in microcontrollers as it has infinite endurance and its incremental semiconductor wafer process cost is relatively low. | In the future, MRAM could potentially be used in microcontrollers as it has infinite endurance and its incremental semiconductor wafer process cost is relatively low. | ||
| - | Volumes[edit] | + | ====Volumes==== |
| In 2002, about 55% of all CPUs sold in the world were 8-bit microcontrollers and microprocessors.[4] Over two billion 8-bit microcontrollers were sold in 1997,[5] and according to Semico, over four billion 8-bit microcontrollers were sold in 2006.[6] More recently, Semico has claimed the MCU market grew 36.5% in 2010 and 12% in 2011.[7] | In 2002, about 55% of all CPUs sold in the world were 8-bit microcontrollers and microprocessors.[4] Over two billion 8-bit microcontrollers were sold in 1997,[5] and according to Semico, over four billion 8-bit microcontrollers were sold in 2006.[6] More recently, Semico has claimed the MCU market grew 36.5% in 2010 and 12% in 2011.[7] | ||
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| A PIC 18F8720 microcontroller in an 80-pin TQFP package. | A PIC 18F8720 microcontroller in an 80-pin TQFP package. | ||
| - | Embedded design[edit] | + | |
| + | ====Embedded design==== | ||
| A microcontroller can be considered a self-contained system with a processor, memory and peripherals and can be used as an embedded system.[13] The majority of microcontrollers in use today are embedded in other machinery, such as automobiles, telephones, appliances, and peripherals for computer systems. | A microcontroller can be considered a self-contained system with a processor, memory and peripherals and can be used as an embedded system.[13] The majority of microcontrollers in use today are embedded in other machinery, such as automobiles, telephones, appliances, and peripherals for computer systems. | ||
| While some embedded systems are very sophisticated, many have minimal requirements for memory and program length, with no operating system, and low software complexity. Typical input and output devices include switches, relays, solenoids, LEDs, small or custom liquid-crystal displays, radio frequency devices, and sensors for data such as temperature, humidity, light level etc. Embedded systems usually have no keyboard, screen, disks, printers, or other recognizable I/O devices of a personal computer, and may lack human interaction devices of any kind. | While some embedded systems are very sophisticated, many have minimal requirements for memory and program length, with no operating system, and low software complexity. Typical input and output devices include switches, relays, solenoids, LEDs, small or custom liquid-crystal displays, radio frequency devices, and sensors for data such as temperature, humidity, light level etc. Embedded systems usually have no keyboard, screen, disks, printers, or other recognizable I/O devices of a personal computer, and may lack human interaction devices of any kind. | ||
| - | Interrupts[edit] | + | ====Interrupts==== |
| Microcontrollers must provide real-time (predictable, though not necessarily fast) response to events in the embedded system they are controlling. When certain events occur, an interrupt system can signal the processor to suspend processing the current instruction sequence and to begin an interrupt service routine (ISR, or "interrupt handler") which will perform any processing required based on the source of the interrupt, before returning to the original instruction sequence. Possible interrupt sources are device dependent, and often include events such as an internal timer overflow, completing an analog to digital conversion, a logic level change on an input such as from a button being pressed, and data received on a communication link. Where power consumption is important as in batteried devices, interrupts may also wake a microcontroller from a low-power sleep state where the processor is halted until required to do something by a peripheral event. | Microcontrollers must provide real-time (predictable, though not necessarily fast) response to events in the embedded system they are controlling. When certain events occur, an interrupt system can signal the processor to suspend processing the current instruction sequence and to begin an interrupt service routine (ISR, or "interrupt handler") which will perform any processing required based on the source of the interrupt, before returning to the original instruction sequence. Possible interrupt sources are device dependent, and often include events such as an internal timer overflow, completing an analog to digital conversion, a logic level change on an input such as from a button being pressed, and data received on a communication link. Where power consumption is important as in batteried devices, interrupts may also wake a microcontroller from a low-power sleep state where the processor is halted until required to do something by a peripheral event. | ||
| - | Programs[edit] | + | ====Programs==== |
| Typically microcontroller programs must fit in the available on-chip memory, since it would be costly to provide a system with external, expandable memory. Compilers and assemblers are used to convert both high-level and assembly language codes into a compact machine code for storage in the microcontroller's memory. Depending on the device, the program memory may be permanent, read-only memory that can only be programmed at the factory, or it may be field-alterable flash or erasable read-only memory. | Typically microcontroller programs must fit in the available on-chip memory, since it would be costly to provide a system with external, expandable memory. Compilers and assemblers are used to convert both high-level and assembly language codes into a compact machine code for storage in the microcontroller's memory. Depending on the device, the program memory may be permanent, read-only memory that can only be programmed at the factory, or it may be field-alterable flash or erasable read-only memory. | ||
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| A customizable microcontroller incorporates a block of digital logic that can be personalized for additional processing capability, peripherals and interfaces that are adapted to the requirements of the application. One example is the AT91CAP from Atmel. | A customizable microcontroller incorporates a block of digital logic that can be personalized for additional processing capability, peripherals and interfaces that are adapted to the requirements of the application. One example is the AT91CAP from Atmel. | ||
| - | Other microcontroller features[edit] | + | ====Other microcontroller features==== |
| Microcontrollers usually contain from several to dozens of general purpose input/output pins (GPIO). GPIO pins are software configurable to either an input or an output state. When GPIO pins are configured to an input state, they are often used to read sensors or external signals. Configured to the output state, GPIO pins can drive external devices such as LEDs or motors, often indirectly, through external power electronics. | Microcontrollers usually contain from several to dozens of general purpose input/output pins (GPIO). GPIO pins are software configurable to either an input or an output state. When GPIO pins are configured to an input state, they are often used to read sensors or external signals. Configured to the output state, GPIO pins can drive external devices such as LEDs or motors, often indirectly, through external power electronics. | ||
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| Universal Asynchronous Receiver/Transmitter (UART) block makes it possible to receive and transmit data over a serial line with very little load on the CPU. Dedicated on-chip hardware also often includes capabilities to communicate with other devices (chips) in digital formats such as Inter-Integrated Circuit (I²C), Serial Peripheral Interface (SPI), Universal Serial Bus (USB), and Ethernet.[14] | Universal Asynchronous Receiver/Transmitter (UART) block makes it possible to receive and transmit data over a serial line with very little load on the CPU. Dedicated on-chip hardware also often includes capabilities to communicate with other devices (chips) in digital formats such as Inter-Integrated Circuit (I²C), Serial Peripheral Interface (SPI), Universal Serial Bus (USB), and Ethernet.[14] | ||
| - | Higher integration[edit] | + | ====Higher integration==== |
| Die of a PIC12C508 8-bit, fully static, EEPROM/EPROM/ROM-based CMOS microcontroller manufactured by Microchip Technology using a 1200 nanometre process. | Die of a PIC12C508 8-bit, fully static, EEPROM/EPROM/ROM-based CMOS microcontroller manufactured by Microchip Technology using a 1200 nanometre process. | ||
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| A micro-controller is a single integrated circuit, commonly with the following features: | A micro-controller is a single integrated circuit, commonly with the following features: | ||
| - | + | - central processing unit - ranging from small and simple 4-bit processors to complex 32-bit or 64-bit processors | |
| - | central processing unit - ranging from small and simple 4-bit processors to complex 32-bit or 64-bit processors | + | - volatile memory (RAM) for data storage |
| - | volatile memory (RAM) for data storage | + | - ROM, EPROM, EEPROM or Flash memory for program and operating parameter storage |
| - | ROM, EPROM, EEPROM or Flash memory for program and operating parameter storage | + | - discrete input and output bits, allowing control or detection of the logic state of an individual package pin |
| - | discrete input and output bits, allowing control or detection of the logic state of an individual package pin | + | - serial input/output such as serial ports (UARTs) |
| - | serial input/output such as serial ports (UARTs) | + | - other serial communications interfaces like I²C, Serial Peripheral Interface and Controller Area Network for system interconnect |
| - | other serial communications interfaces like I²C, Serial Peripheral Interface and Controller Area Network for system interconnect | + | - peripherals such as timers, event counters, PWM generators, and watchdog |
| - | peripherals such as timers, event counters, PWM generators, and watchdog | + | - clock generator - often an oscillator for a quartz timing crystal, resonator or RC circuit |
| - | clock generator - often an oscillator for a quartz timing crystal, resonator or RC circuit | + | - many include analog-to-digital converters, some include digital-to-analog converters |
| - | many include analog-to-digital converters, some include digital-to-analog converters | + | - in-circuit programming and in-circuit debugging support |
| - | in-circuit programming and in-circuit debugging support | + | - This integration drastically reduces the number of chips and the amount of wiring and circuit board space that would be needed to produce equivalent systems using separate chips. Furthermore, on low pin count devices in particular, each pin may interface to several internal peripherals, with the pin function selected by software. This allows a part to be used in a wider variety of applications than if pins had dedicated functions. |
| - | This integration drastically reduces the number of chips and the amount of wiring and circuit board space that would be needed to produce equivalent systems using separate chips. Furthermore, on low pin count devices in particular, each pin may interface to several internal peripherals, with the pin function selected by software. This allows a part to be used in a wider variety of applications than if pins had dedicated functions. | + | |
| Micro-controllers have proved to be highly popular in embedded systems since their introduction in the 1970s. | Micro-controllers have proved to be highly popular in embedded systems since their introduction in the 1970s. | ||
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| Microcontrollers typically do not have a math coprocessor, so floating point arithmetic is performed by software. | Microcontrollers typically do not have a math coprocessor, so floating point arithmetic is performed by software. | ||
| - | Programming environments[edit] | + | ====Programming environments==== |
| Microcontrollers were originally programmed only in assembly language, but various high-level programming languages are now also in common use to target microcontrollers. These languages are either designed specially for the purpose, or versions of general purpose languages such as the C programming language. Compilers for general purpose languages will typically have some restrictions as well as enhancements to better support the unique characteristics of microcontrollers. Some microcontrollers have environments to aid developing certain types of applications. Microcontroller vendors often make tools freely available to make it easier to adopt their hardware. | Microcontrollers were originally programmed only in assembly language, but various high-level programming languages are now also in common use to target microcontrollers. These languages are either designed specially for the purpose, or versions of general purpose languages such as the C programming language. Compilers for general purpose languages will typically have some restrictions as well as enhancements to better support the unique characteristics of microcontrollers. Some microcontrollers have environments to aid developing certain types of applications. Microcontroller vendors often make tools freely available to make it easier to adopt their hardware. | ||
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| Recent microcontrollers are often integrated with on-chip debug circuitry that when accessed by an in-circuit emulator via JTAG, allow debugging of the firmware with a debugger. A real-time ICE may allow viewing and/or manipulating of internal states while running. A tracing ICE can record executed program and MCU states before/after a trigger point. | Recent microcontrollers are often integrated with on-chip debug circuitry that when accessed by an in-circuit emulator via JTAG, allow debugging of the firmware with a debugger. A real-time ICE may allow viewing and/or manipulating of internal states while running. A tracing ICE can record executed program and MCU states before/after a trigger point. | ||
| - | Types of microcontrollers[edit] | + | ====Types of microcontrollers==== |
| See also: List of common microcontrollers | See also: List of common microcontrollers | ||
| As of 2008, there are several dozen microcontroller architectures and vendors including: | As of 2008, there are several dozen microcontroller architectures and vendors including: | ||
| - | ARM core processors (many vendors) | + | - ARM core processors (many vendors) |
| - | ARM Cortex-M cores are specifically targeted towards microcontroller applications | + | - ARM Cortex-M cores are specifically targeted towards microcontroller applications |
| - | Atmel AVR (8-bit), AVR32 (32-bit), and AT91SAM (32-bit) | + | - Atmel AVR (8-bit), AVR32 (32-bit), and AT91SAM (32-bit) |
| - | Cypress Semiconductor's M8C Core used in their PSoC (Programmable System-on-Chip) | + | - Cypress Semiconductor's M8C Core used in their PSoC (Programmable System-on-Chip) |
| - | Freescale ColdFire (32-bit) and S08 (8-bit) | + | - Freescale ColdFire (32-bit) and S08 (8-bit) |
| - | Freescale 68HC11 (8-bit), and others based on the Motorola 6800 family | + | - Freescale 68HC11 (8-bit), and others based on the Motorola 6800 family |
| - | Intel 8051, also manufactured by NXP Semiconductors, Infineon and many others | + | - Intel 8051, also manufactured by NXP Semiconductors, Infineon and many others |
| - | Infineon: 8-bit XC800, 16-bit XE166, 32-bit XMC4000 (ARM based Cortex M4F), 32-bit TriCore and, 32-bit Aurix Tricore Bit microcontrollers[18] | + | - Infineon: 8-bit XC800, 16-bit XE166, 32-bit XMC4000 (ARM based Cortex M4F), 32-bit TriCore and, 32-bit Aurix Tricore Bit microcontrollers[18] |
| - | MIPS | + | - MIPS |
| - | Microchip Technology PIC, (8-bit PIC16, PIC18, 16-bit dsPIC33 / PIC24), (32-bit PIC32) | + | - Microchip Technology PIC, (8-bit PIC16, PIC18, 16-bit dsPIC33 / PIC24), (32-bit PIC32) |
| - | NXP Semiconductors LPC1000, LPC2000, LPC3000, LPC4000 (32-bit), LPC900, LPC700 (8-bit) | + | - NXP Semiconductors LPC1000, LPC2000, LPC3000, LPC4000 (32-bit), LPC900, LPC700 (8-bit) |
| - | Parallax Propeller | + | - Parallax Propeller |
| - | PowerPC ISE | + | - PowerPC ISE |
| - | Rabbit 2000 (8-bit) | + | - Rabbit 2000 (8-bit) |
| - | Renesas Electronics: RL78 16-bit MCU; RX 32-bit MCU; SuperH; V850 32-bit MCU; H8; R8C 16-bit MCU | + | - Renesas Electronics: RL78 16-bit MCU; RX 32-bit MCU; SuperH; V850 32-bit MCU; H8; R8C 16-bit MCU |
| - | Silicon Laboratories Pipelined 8-bit 8051 Microcontrollers and mixed-signal ARM-based 32-bit microcontrollers | + | - Silicon Laboratories Pipelined 8-bit 8051 Microcontrollers and mixed-signal ARM-based 32-bit microcontrollers |
| - | STMicroelectronics STM8 (8-bit), ST10 (16-bit) and STM32 (32-bit) | + | - STMicroelectronics STM8 (8-bit), ST10 (16-bit) and STM32 (32-bit) |
| - | Texas Instruments TI MSP430 (16-bit), MSP432 (32-bit), C2000 (32-bit) | + | - Texas Instruments TI MSP430 (16-bit), MSP432 (32-bit), C2000 (32-bit) |
| - | Toshiba TLCS-870 (8-bit/16-bit) | + | - Toshiba TLCS-870 (8-bit/16-bit) |
| Many others exist, some of which are used in very narrow range of applications or are more like applications processors than microcontrollers. The microcontroller market is extremely fragmented, with numerous vendors, technologies, and markets. Note that many vendors sell or have sold multiple architectures. | Many others exist, some of which are used in very narrow range of applications or are more like applications processors than microcontrollers. The microcontroller market is extremely fragmented, with numerous vendors, technologies, and markets. Note that many vendors sell or have sold multiple architectures. | ||
| - | Interrupt latency[edit] | + | ====Interrupt latency==== |
| In contrast to general-purpose computers, microcontrollers used in embedded systems often seek to optimize interrupt latency over instruction throughput. Issues include both reducing the latency, and making it be more predictable (to support real-time control). | In contrast to general-purpose computers, microcontrollers used in embedded systems often seek to optimize interrupt latency over instruction throughput. Issues include both reducing the latency, and making it be more predictable (to support real-time control). | ||
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| Other factors affecting interrupt latency include: | Other factors affecting interrupt latency include: | ||
| + | - Cycles needed to complete current CPU activities. To minimize those costs, microcontrollers tend to have short pipelines (often three instructions or less), small write buffers, and ensure that longer instructions are continuable or restartable. RISC design principles ensure that most instructions take the same number of cycles, helping avoid the need for most such continuation/restart logic. | ||
| + | - The length of any critical section that needs to be interrupted. Entry to a critical section restricts concurrent data structure access. When a data structure must be accessed by an interrupt handler, the critical section must block that interrupt. Accordingly, interrupt latency is increased by however long that interrupt is blocked. When there are hard external constraints on system latency, developers often need tools to measure interrupt latencies and track down which critical sections cause slowdowns. | ||
| + | - One common technique just blocks all interrupts for the duration of the critical section. This is easy to implement, but sometimes critical sections get uncomfortably long. | ||
| + | - A more complex technique just blocks the interrupts that may trigger access to that data structure. This is often based on interrupt priorities, which tend to not correspond well to the relevant system data structures. Accordingly, this technique is used mostly in very constrained environments. | ||
| + | - Processors may have hardware support for some critical sections. Examples include supporting atomic access to bits or bytes within a word, or other atomic access primitives like the LDREX/STREX exclusive access primitives introduced in the ARMv6 architecture. | ||
| + | - Interrupt nesting. Some microcontrollers allow higher priority interrupts to interrupt lower priority ones. This allows software to manage latency by giving time-critical interrupts higher priority (and thus lower and more predictable latency) than less-critical ones. | ||
| + | - Trigger rate. When interrupts occur back-to-back, microcontrollers may avoid an extra context save/restore cycle by a form of tail call optimization. | ||
| + | - Lower end microcontrollers tend to support fewer interrupt latency controls than higher end ones. | ||
| - | Cycles needed to complete current CPU activities. To minimize those costs, microcontrollers tend to have short pipelines (often three instructions or less), small write buffers, and ensure that longer instructions are continuable or restartable. RISC design principles ensure that most instructions take the same number of cycles, helping avoid the need for most such continuation/restart logic. | + | ====Microcontroller embedded memory technology==== |
| - | The length of any critical section that needs to be interrupted. Entry to a critical section restricts concurrent data structure access. When a data structure must be accessed by an interrupt handler, the critical section must block that interrupt. Accordingly, interrupt latency is increased by however long that interrupt is blocked. When there are hard external constraints on system latency, developers often need tools to measure interrupt latencies and track down which critical sections cause slowdowns. | + | |
| - | One common technique just blocks all interrupts for the duration of the critical section. This is easy to implement, but sometimes critical sections get uncomfortably long. | + | |
| - | A more complex technique just blocks the interrupts that may trigger access to that data structure. This is often based on interrupt priorities, which tend to not correspond well to the relevant system data structures. Accordingly, this technique is used mostly in very constrained environments. | + | |
| - | Processors may have hardware support for some critical sections. Examples include supporting atomic access to bits or bytes within a word, or other atomic access primitives like the LDREX/STREX exclusive access primitives introduced in the ARMv6 architecture. | + | |
| - | Interrupt nesting. Some microcontrollers allow higher priority interrupts to interrupt lower priority ones. This allows software to manage latency by giving time-critical interrupts higher priority (and thus lower and more predictable latency) than less-critical ones. | + | |
| - | Trigger rate. When interrupts occur back-to-back, microcontrollers may avoid an extra context save/restore cycle by a form of tail call optimization. | + | |
| - | Lower end microcontrollers tend to support fewer interrupt latency controls than higher end ones. | + | |
| - | + | ||
| - | Microcontroller embedded memory technology[edit] | + | |
| Since the emergence of microcontrollers, many different memory technologies have been used. Almost all microcontrollers have at least two different kinds of memory, a non-volatile memory for storing firmware and a read-write memory for temporary data. | Since the emergence of microcontrollers, many different memory technologies have been used. Almost all microcontrollers have at least two different kinds of memory, a non-volatile memory for storing firmware and a read-write memory for temporary data. | ||
| - | Data[edit] | + | ====Data==== |
| From the earliest microcontrollers to today, six-transistor SRAM is almost always used as the read/write working memory, with a few more transistors per bit used in the register file. FRAM or MRAM could potentially replace it as it is 4 to 10 times denser which would make it more cost effective. | From the earliest microcontrollers to today, six-transistor SRAM is almost always used as the read/write working memory, with a few more transistors per bit used in the register file. FRAM or MRAM could potentially replace it as it is 4 to 10 times denser which would make it more cost effective. | ||
| In addition to the SRAM, some microcontrollers also have internal EEPROM for data storage; and even ones that do not have any (or not enough) are often connected to external serial EEPROM chip (such as the BASIC Stamp) or external serial flash memory chip. | In addition to the SRAM, some microcontrollers also have internal EEPROM for data storage; and even ones that do not have any (or not enough) are often connected to external serial EEPROM chip (such as the BASIC Stamp) or external serial flash memory chip. | ||
| - | A few recent microcontrollers beginning in 2003 have "self-programmable" flash memory.[3] | + | A few recent microcontrollers beginning in 2003 have "self-programmable" flash memory. |
| - | Firmware[edit] | + | ====Firmware==== |
| The earliest microcontrollers used mask ROM to store firmware. Later microcontrollers (such as the early versions of the Freescale 68HC11 and early PIC microcontrollers) had quartz windows that allowed ultraviolet light in to erase the EPROM. | The earliest microcontrollers used mask ROM to store firmware. Later microcontrollers (such as the early versions of the Freescale 68HC11 and early PIC microcontrollers) had quartz windows that allowed ultraviolet light in to erase the EPROM. | ||
| The Microchip PIC16C84, introduced in 1993,[19] was the first microcontroller to use EEPROM to store firmware. In the same year, Atmel introduced the first microcontroller using NOR Flash memory to store firmware.[3] | The Microchip PIC16C84, introduced in 1993,[19] was the first microcontroller to use EEPROM to store firmware. In the same year, Atmel introduced the first microcontroller using NOR Flash memory to store firmware.[3] | ||
| - | See also[edit] | + | ====See also==== |
| - | Portal icon Electronics portal | + | * Portal icon Electronics portal |
| - | List of common microcontrollers | + | * List of common microcontrollers |
| - | List of open-source hardware projects | + | * List of open-source hardware projects |
| - | Microbotics | + | * Microbotics |
| - | MCU with built in WiFi | + | * MCU with built in WiFi |
| - | Programmable logic controller | + | * Programmable logic controller |
| - | Single-board microcontroller | + | * Single-board microcontroller |