APPLE CRAPPLE

Serial Cable I spent a few minutes continuity testing the P3 card edge connector for the serial port so that I could build a serial cable f...

I recently acquired a Synertek MBC020 EXORbus single board computer, notably sporting a 6512 microprocessor. The 6512 is software compatibl...

It did not take long for me to realize that the virtual address jumper board for my MIKUL 6218 was not a great long-term soloution. It was ...

I received some membrane keypads in the mail today. Unfortunately, I neglected to order the 4x5 Keypads I hoped to use and only ordered 4x4 ...

By using the HCF instruction and a cheap logic analyzer , I was able to make a memory map of the MIKUL 6809-5: ↑ External &nbsp ...

I previously documented my ultimately successful attempt to reverse engineer the CMS 9619 Advanced Single Board Computer . The main goal wa...

I recently procured another EXORbus processor board, the MIKUL 6809-5, for a reasonable price. Let's take a look... Notable ICs: Motor...

Well, I ended up having a very busy October (baby is due November 1st!), so I didnt get much done for RetroChallenge. I kept looking for a Z...

Well, with virtually no hope of getting a serial cable for my Zaurus, I moved on to some other bits that the Z needs. Really soon after I bo...

About the Sharp Zaurus SL-5500 Before I begin with details on my project, here is some background on the Sharp Zaurus, as it was relatively...

Well, I had hoped to do some work on an Apple II project, but my theme category for RC2021/10 "The Millennials" isn't getting ...

In my previous post on the MIKUL 6218 board, I mentioned that was using the lower 32K of address space on the CMS 9619 to swap in 16 banks o...

With the virtual address jumper for the MIKUL 6218 sorted , I still needed to simplify the address decoding and memory chip selects so that ...

A18 Addition I really want to use my two 512KiB SRAM chips on this board to maximize the usable RAM. Fortunately, the MIKUL 6218 has 32 pin...

I was recently able to trade one of my extra CMS 9619 SBCs for a CMS 9600A MPU (Thanks Joel!). This EXORbus processor card has very sim...

I haven't spent much time working on my CMS 9639 SBC because, unlike the CMS 9619 , it does not have any usable on-board RAM and does n...

One of the shortcomings of this CMS 9619 system is the fairly complicated OS9 bootstrap procedure I had to use in the absence of any sort of...

After finding out that my CMS 9619 Advanced Single Board MicroComputer was having problems accessing the EXORbus , I tried some trouble shoo...

Update : Since this post I have figured out how to change the address map using a GAL IC. I recently posted some minor hardware modificati...

I finally got drivewire running on the CMS 9619 SBC. As a result, I managed to complete the bootup and have a virtual disk! Source code a...