Vintage Computers


Upgrading CPUVille SBC ROM

Introduction to Upgrading CPUVille SBC ROM In this section, we’ll walk through the process of Upgrading CPUVille SBC ROM to version 15. This is a Z80 Computer which was designed by Donn Stewart. You can purchase the computer, and the bus display kit (slow board) from the CPUVille website. It Read More »

Upgrading CPUVille SBC ROM

1802 Membership Card Timer

Introduction to the 1802 Membership Card Timer In this section, we’ll crate a scan based 1802 Membership Card Timer using BASIC3. The 1802 Membership card uses the COSMAC 1802 Processor. Since we are basing the timer on the scan rate, you may have to vary the delay loops to calibrate Read More »

1802 Membership Card Timer

COSMAC 1802 I/O Operations

Introduction to COSMAC 1802 I/O Operations COSMAC 1802 I/O Operations allow us to get data from an input port, and write data to an output port. In this case, I’m using the 1802 membership card. On the 1802 Membership Card, we use Port 4 for both the switches and the Read More »

COSMAC 1802 I/O Operations

Assembly Programming Tips

Introduction to Assembly Programming Tips In this section, I’m compiling a list of Assembly Programming Tips. Mainly, this is for manipulating data in assembly language. Most of these methods will work with any processor. It’s important to realize, though, that you might have special instructions in some processors that handle Read More »

Assembly Programming Tips

6502 Stack Operations

Introduction to 6502 Stack Operations 6502 Stack Operations are very useful in programming. You can temporarily store data that you need to retrieve later. Specifically, we might use the stack when calling subroutines in the 6502. We might back up register data that we need to retrieve later on. The Read More »

6502 Stack Operations

Add Programs to an IMSAI Disk

How to Add Programs to an IMSAI Disk There are several methods to Add Programs to an IMSAI Disk. One way is to use XModem, which is a bit time consuming for many files. Another way is to add the files to an image using CPMTOOLS, which is the method Read More »

Add Programs to an IMSAI Disk

Connecting to the PAL-1 Computer

Introduction: Connecting to the PAL-1 Computer When Connecting to the PAL-1 Computer, we need a straight serial cable. That is to say, pin 2 on one end of the cable connects to pin 2 on the other end. Pin 3 on one end, connects to pin 3 on the other Read More »

Connecting to the PAL-1 Computer

Inverting Q on the ELF MC

Introduction to Inverting Q on the ELF MC Certain firmware requires Inverting Q on the ELF MC (1802 ELF Membership Card). This is usually true when you have the front panel attached, which is revision J or later. In my case, I wanted to run Diskless ELF/OS (and still have Read More »

Inverting Q on ELF MC

How to Burn an EPROM

Introduction — How to Burn an EPROM In this section, we’ll discuss How to Burn an EPROM. In this case, I have an ST27C256 EPROM. I will be placing the ELF2K firmware on this module for my COSMAC Membership card. I’m using the T48 EPROM Programmer, along with it’s own Read More »

How to Burn an EPROM

Backup Your CPUVille Z80 Drive

How to Backup Your CPUVille Z80 Drive containing CP/M. In this post, we’ll discuss how to Backup Your CPUVille Z80 Drive (with CP/M). Setting up a Z80 machine with CP/M can be a lot of work. First you have to find all of the files you need. After that you Read More »

Backup Your CPUVille Z80 Drive