This MCU from Microchip has been around since 1998 and is the successor to the very first serially programmable PIC, the PIC16C84. The PIC16F84A is often the starting point for learning PIC microcontrollers because it only has 35 assembly language instructions and it only costs less than $5 a piece. Creating a serial programmer for this microcontroller also won’t take a lot of time.

The PIC16F84A

Here’s the specifications of the PIC16F84A:

• Bus width – 8 bits
• Pin Count – 18 (PDIP, SOIC) / 20 (SSOP)
• Program Memory – 1750 bytes
• CPU Speed – 5 million instructions per second
• RAM Size – 68 bytes
• EEPROM Size – 64 bytes

The PIC16F84A is an 8-bit device which means almost all of its registers are 8 bits wide.

Program memory size tells you how much code can you burn inside the microcontroller. 1750 bytes of program memory is enough for simple applications which is where the PIC16F84A is common.