Reverse engineering an Argentine MSX

The Talent DPC-200 is an MSX home computer manufactured in Argentina during the 1980s.

Like many locally produced computers from that period, detailed board-level documentation is difficult to find. Schematics are incomplete or unavailable, and different hardware revisions exist.

My goal with this project is to document the original DPC-200 hardware directly from the physical motherboard.

Rather than recreating only a conventional schematic, I wanted to preserve the relationship between the electrical circuit and the actual PCB.

Starting from the physical board

The reverse-engineering process started with high-resolution photographs of both sides of the motherboard.

Components were identified and positioned over the photographs. From there, the copper traces were followed manually and the connections between IC pins, connectors and discrete components were reconstructed.

Each continuous electrical connection is stored as a net.

For example, instead of only knowing where a trace appears in a photograph, the project can represent a connection as structured data linking all the pins that belong to the same electrical node.

This gradually turned the physical motherboard into a machine-readable description of the circuit.

Building an interactive PCB explorer

Once enough components and nets had been reconstructed, I built a web-based viewer to explore the data directly over the original motherboard photographs.

The viewer is available at:

https://dpc200.com.ar

It allows you to:

  • Locate components on the physical board
  • Search for ICs and other parts
  • Highlight individual electrical nets
  • Follow connections directly over the PCB
  • Inspect the pins belonging to a net
  • Navigate between connected components
  • Browse the component database and BOM
  • Generate direct links to highlighted areas of the motherboard

The idea is to make the PCB itself part of the documentation.

Instead of reading a netlist separately and then trying to locate those connections on the board, the electrical information can be explored visually in its original physical context.

Preserving the original visual identity

The visual design of dpc200.com.ar is deliberately inspired by the original Talent DPC-200 packaging, including its typography, color bands and overall graphic style.

The intention is to preserve not only the hardware, but also part of the visual identity associated with the original computer.

From PCB traces to circuit analysis

The reconstructed connectivity also makes it possible to investigate individual sections of the computer.

For example, the data can be used to trace:

  • The Z80 address and data buses
  • Memory connections
  • Slot selection logic
  • I/O decoding
  • Wait-state generation
  • Keyboard interface
  • Reset circuitry
  • Video circuitry
  • Audio paths
  • Expansion connectors

As the reverse engineering progresses, these subsystems can be documented independently while still remaining linked to their exact physical location on the original motherboard.

Using structured data with AI

An unexpected result of the project is that the reconstructed motherboard can also be represented in a form that an AI model can analyze.

Instead of asking an AI to guess connections from a PCB photograph, the viewer can generate structured information describing components, pins and electrical nets.

That data can then be supplied together with questions such as:

How is the system clock generated?

Which logic generates the slot selection signals?

What components are connected to this Z80 data line?

How is the keyboard matrix read?

The AI is therefore working from the reconstructed electrical connectivity rather than trying to infer the circuit visually.

I am experimenting with this as another way to explore and document vintage hardware.

Additional motherboard revision

The viewer also includes a second DPC-200 motherboard based on data from Rodrigo Pelorosso's pcb-tracer project.

Many thanks to Rodrigo for making his reverse-engineering work...

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