PIC16F84A 18-pin Enhanced Flash/EEPROM 8-Bit MCU Data Sheet

PIC16F84A1.0 DEVICE OVERVIEWThis document contains device-specific information forthe operation of the PIC16F84A device. Additionalinformation may be found in the PICmicro Mid-RangeReference Manual, (DS33023), which may be downloadedfrom the Microchip website. The ReferenceManual should be considered a complementary documentto this data sheet, and is highly recommendedreading for a better understanding of the device architectureand operation of the peripheral modules.The PIC16F84A belongs to the mid-range family of thePICmicro microcontroller devices. A block diagram ofthe device is shown in Figure 1-1.The program memory contains 1K words, which translatesto 1024 instructions, since each 14-bit programmemory word is the same width as each device instruction.The data memory (RAM) contains 68 bytes. DataEEPROM is 64 bytes.There are also 13 I/O pins that are user-configured ona pin-to-pin basis. Some pins are multiplexed with otherdevice functions. These functions include:• External interrupt• Change on PORTB interrupt• Timer0 clock inputTable 1-1 details the pinout of the device with descriptionsand details for each pin.FIGURE 1-1:PIC16F84A BLOCK DIAGRAMFlashProgramMemoryPIC16F84A1K x 1413Program Counter8 Level Stack(13-bit)Data BusRAMFile RegistersPIC16F84A68 x 88EEPROM Data MemoryEEDATAEEPROMData Memory64 x 8ProgramBus14Instruction reg7Addr MuxRAM AddrEEADR5Direct Addr7IndirectAddrTMR0FSR reg8STATUS regRA4/T0CKIInstructionDecode &ControlPower-upTimerOscillatorStart-up TimerPower-onResetALUMUX8I/O PortsRA3:RA0TimingGenerationWatchdogTimerW regRB7:RB1RB0/INTOSC2/CLKOUTOSC1/CLKINMCLRVDD, VSS© 1998 Microchip Technology Inc. Preliminary DS35007A-page 3