DEC Opcodes

Big iron in your pocket! All the information you need on DEC's series of influential computers, including coding lessons and real-world locations to see them for real.

Dec Opcodes – DEC Architecture Reference

Before the microprocessor, there was DEC. The minicomputers built by Digital Equipment Corporation didn't just advance computing - they defined it. Unix was born on a PDP-7. Spacewar! ran on a PDP-1. The field of Artificial Intelligence was born on the PDP-10. The VAX powered universities and research labs worldwide for a generation.

DecOpcodes puts the complete instruction sets of these legendary machines in your pocket.

Five iconic architectures covered: PDP-1 (1960) · PDP-8 (1965) · PDP-10 (1966) · PDP-11 (1970) · VAX (1977)

For every instruction: 

• Full description of what the instruction does  • Octal and hex encoding  • Flags affected  • Addressing modes, word count, and cycle counts  • Assembly code examples and implementation notes

But there is a lot more than just dry opcodes: 

• Complete system specifications and register architecture  • Historical context and cultural impact  • Archival photographs - front panels, system cabinets, and more  • Notable installations and the systems they powered  • Architecture variants and successors • Interactive lessons on assembly language and console operations (ideal if you have an PiDP emulator)

Built for exploration: 

• Search across all systems instantly • A simple assembler for PDP-1, -8 and -11 code • Filter by instruction category  • Sort alphabetically or by category • Favorite instructions for quick reference

Beautifully designed: 

• System-specific accent colours  • Five themes including Terminal green and Blinkenlights orange  • Full Dark Mode support

From the 18-bit simplicity of the PDP-1 to the 32-bit sophistication of the VAX, DecOpcodes is a fascinating and interactive journey through the machines that made modern computing possible.

All features are free and unlocked. If you like the app you can always leave a nice review or tip the developer!