Editing PIC microcontrollers (section)

==Hardware features==
PIC devices generally feature:

* Flash memory (program memory, programmed using [[MPLAB devices]])
* SRAM (data memory)
* [[EEPROM]] (programmable at run-time)
* Sleep mode (power savings)
* [[Watchdog timer]]
* Various crystal or [[RC circuit|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:
* [[GPIO|General purpose I/O pins]]
* Internal clock oscillators
* 8/16/32&nbsp;bit timers
* Synchronous/Asynchronous Serial Interface [[USART]]
* MSSP Peripheral for [[I²C]] and [[Serial Peripheral Interface|SPI]] communications
* Capture/Compare and [[pulse-width modulation|PWM]] modules
* [[Analog-to-digital converter]]s (up to ~1.0 Msps)
* USB, [[Ethernet]], [[Controller Area Network|CAN]] interfacing support
* External memory interface
* Integrated analog RF front ends (PIC16F639, and rfPIC)<!-- Carrier frequency? -->.
* [[KeeLoq|KEELOQ]] Rolling code encryption peripheral (encode/decode)
* And many more

===Trends===
The first generation of PICs with [[EPROM]] storage have been almost completely 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 Likewise, the original 12-bit instruction set of the PIC1650 and its direct descendants has been superseded by 14-bit and 16-bit instruction sets.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-erasable) versions of some of its EPROM based PICs for legacy support or volume orders. The Microchip website lists PICs that are not electrically erasable as OTP. UV erasable windowed versions of these chips can be ordered.

===Part number===
The F in a PICMicro part number generally indicates the PICmicro uses flash memory and can be erased electronically. Conversely, 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.

An L in the name indicates the part will run at a lower voltage, often with frequency limits imposed.<ref name="3vdesign">{{cite web | title=3V Design Center | url=http://www.microchip.com/stellent/idcplg?IdcService=SS_GET_PAGE&nodeId=2530 | access-date=2 August 2011}}</ref> Parts designed specifically for low voltage operation, within a strict range of 3 – 3.6 volts, are marked with a J in the part number. These parts are also uniquely I/O tolerant as they will accept up to 5&nbsp;V as inputs.<ref name="3vdesign" />