Some Disassembly Required

Building, Un-building and Re-building Things

Category: Digital logic

  • The 6502 Single Board Development System

    The 6502 Single Board Development System

    Building An All-In-One 6502 Development Board

  • Hexadecimal Value Display for 16 Bit Logic Input

    Hexadecimal Value Display for 16 Bit Logic Input

    Designing and Building a Hexadecimal Display for Small Computer and Logic Projects. I do digital design regularly, and it’s occasionally real handy to take a group of signals (e.g. an address bus) and display them. I don’t have a lot of great tools to do that though. Ordinarily I’d hook up my logic analyzer. That…

  • Discrete VGA Graphics Adapter: Framebuffer and DAC

    Discrete VGA Graphics Adapter: Framebuffer and DAC

    Putting Actual Graphics Into the Graphics Adapter Last time, I threw together a VGA time base. I didn’t spend much time elaborating on it, because honestly it bores me. There is only so much you can say about a counter that hasn’t already been said. This time around the goal is to display an actual…

  • Discrete PS/2 Keyboard Interface

    Discrete PS/2 Keyboard Interface

    Type Like it’s 1987: a Hardware Driven PS/2 Interface. In 1987 IBM released the PS/2 keyboard, an update of the earlier IBM AT keyboard with a smaller connector, extra features, and support for a mouse using the same connector and protocol. This rapidly became the standard for PC compatibles. You’ll still find PS/2 ports on…