rehsd

As I have gotten my 386 DX upper and lower motherboard PCBs working -- at least to the point of validating much of the design -- I am now...

Picking up from 80386 DX Build (rehsdonline.com), I am transitioning my 386 DX build to an EATX form factor, incorporating changes up to...

For my 286 to 386SX upgrade interposer PCB, I need to implement logic for S0# and S1# (along with a few other signals). For my 386DX...

While I continue to build out my 286 (386 SX) system, I thought I would start learning more about the 80386 DX. I am hoping to have a...

I'm looking into a 386SX upgrade for my 286 build. The Intel 386 Hardware Reference Manual includes the following schematic for...

I am researching how to add additional RAM to my 286 build. I started by thinking about a memory expansion card for my system. That has...

I now have FreeDOS running on my 286 build. In this running post, I'll add information about incremental updates I am doing. In the...

Back in January of this year, I posted a list of potential roadmap items for my 26 build. See 80286 System Roadmap (rehsdonline.com). As...

As I continue to work towards getting FreeDOS running on my 286 homebrew build, I am encountering a new issue. During boot, the FreeDOS...

I am running into an issue getting expected CPU flags register values back from interrupt calls made in FreeDOS to my BIOS on my 286...

In this post, I will share a bit about the development environment I am using to build FreeDOS (and possibly other DOS applications). I...

At this stage of my homebrew 286 system build, I have an IDE interface to a compact flash (CF) card. I have begun implementing disk...

I am currently working to see if I can boot to an IDE storage device (specifically, a CF Card) and get FreeDOS's kernel loaded. I'll use...

I am nearly six months into my 286 project. While I started on breadboards, I am now at a nice stage where I have an ATX form-factor...

I am starting to implement support for additional interrupts on my 286 system. This includes BIOS interrupts and DOS interrupts. Relevant...

Up to this point, all code running on my 286 system has been x86 assembly (real mode). I am hoping to learn how to compile C or C++ code...

A helpful feature that I am looking to add to my 286 system is onboard flash ROM updates, where I do not need to remove the flash ROMs to...

For my sound card, I plan to leverage previous work that I did for my 65816 system build. I will refactor the sound card to support my...

My 286 system does not have built-in mouse support (yet). I have been experimenting with a few options. Back on my 6502 system, I added...

Last October (2022), I started my learning journey to develop a 286 system. See Start to an 80286 System. As of this writing, I have a...