Note: The Prototype PLD Card is supplied in Kitset form only (assembly required). The base price is for the double-sided silkscreened Prototype PLD Card PCB ONLY. The optional packs are required to make a complete Prototype PLD Card Kitset. If you already have the required components, then you can just order the PCB only.

What is Minimalist Europe Card Bus

Europe Card Bus (ECB) is a Retro CPU Bus standard from the late 1970’s / early 1980’s.

The “Minimalist Europe Card Bus” (as I’ve called it), is a Retro 8-bit CPU Bus and PCB design standard that I decided to define & document. The purpose of which is to provide a modular platform for me to re-experience the fun of experimenting with the different 8-bit CPU’s, and the various video and peripheral devices, that I grew up with in the late 1970’s and early 1980’s.

My goal is that of a robust and modular design platform which allows me to create interchangeable PCB cards, based on time proven reliable bus connectors and modern low-cost prototype PCB manufacturing.

i.e. A robust, flexible, and low cost way for me to re-create some of the early microprocessor circuits, that I’d originally built using Wire-Wrap methods back in the day.

As evident from the name, the Bus itself is based on a Minimalist implementation of the original Europe Card Bus (ECB) standard.

Standardised Mechanical Specification for a Minimalist ECB “MECB” Board

MECB Standardised Board Design Parameters:

• Satisfy the 100mm square maximum board size, for low-cost prototype PCB manufacturing.
• Utilise the lower cost 64-pin (Row A&C) robust and reliable DIN 41612 type C connectors, for cost saving.
• Ensure the DIN 41612 connector(s) can be easily centred across the board width, grid aligned.
• Provide two standardised corner holes, on the edge opposing the right-angle DIN connector, to allow for attachment of card handles (to ease board insertion & extraction), or for board mounting – refer next point.
• Provide an additional two standardised corner mounting holes on the edge with the right-angle DIN connector, to provide a full set of four corner holes (to allow for stand-alone board mounting).
• Standardise PCB corner rounding, for sharp corner removal consistency across all boards & visual tidiness.

MECB Standardised Board Design Notes:

• PCB layout is designed utilising 0.127mm (5.0 mils) grid setting.
• Board size is 99.822mm, which represents the greatest even multiple of 0.127mm (i.e. multiple of 0.254mm – 10.0 mils), that will fit within the desired maximum 100mm board dimension.
• Standard M3 sized mounting holes were chosen. An additional two mid-edge located mounting holes are specified for the Backplane board only (to provide additional mechanical support).
• For reference, DIN 41612 connectors can utilise standard M2.5 mounting bolts (8mm length for the straight connectors, 10mm length for right angle connectors).
• Implemented as a KiCAD Template, to assist with simplifying the creation of each new MECB board design.

Please refer to the attached photo outlining all dimensions for the MECB Standardised Board Mechanical Specifications.

Prototype PLD Card Design

Prototype PLD Card Design Parameters:

• All dimensions and corner mounting holes, as per the MECB Standardised Board Mechanical Specification.
• A 64-pin header, clearly labelled with the A & C rows and pins 1 – 32, for ease of access to all bus signals.
• Power bus bars along the two sides of the card, to distribute the +5V and Ground power connections.
• A MECB standardised PLD glue-logic chip to provide 3 Chip Selects (CS0, CS1, CS2)
• All remaining board space (with exception of mounting hole clearance), utilised for through-hole pads, in a 0.1″ perf-board style grid.
• With the exception of the top edge 3 rows (see below), all grid holes are connected in groups of 3, to facilitate easy wiring of 0.3" and 0.6" DIP packaged IC's.
• 3 rows of grid holes at the top edge of the board form a simple non-connected grid, to facilitate mounting 0.1" pin profile board connectors.

This Prototype PLD Card enhances the existing MECB Prototype Card (see seperate listing), with the addition of the glue-logic PLD chip to simplify prototyping new MECB I/O cards etc.

What You Get

To satisfy everyone's differing needs, I've split the Prototype PLD Card Kitset into Optional Add-on Packs.

Firstly, note that the base price is for the double-sided silkscreened Prototype PLD Card PCB Only.

Then you add the optional packs to complete the Kitset, depending on your parts requirements.

Optional Hardware Pack includes:

• 1x Right-Angle Male DIN41612 364 Keyed Bus Connector
• 2x M2.5 Stainless Steel Bolt 10mm (2 required for Right-Angle Connector)
• 2x M2.5 Stainless Steel Hexagonal Nut (for above Bolts)
• 2x 40 pin PCB Headers (to be cut into 2x 32 pin and 1x 3 pin headers)
• 4x 12mm Nylon PCB Spacer
• 8x 6mm Nylon Bolt (for Spacer mounting)

Optional Component Pack includes:

• 1x 20 pin Zero Insertion Force (ZIF) IC Socket
• ATF16V8 PLD Chip Tested and Programmed as per the linked Video (i.e. CS0 $E0-$E7, CS1 $E8-$EF, CS2 $F0-$F7 I/O Address ranges).
• 0.1uf Bypass Capacitor

BONUS: If you order both Optional Packs (to make a Complete Kitset), I'll include a laminated full colour MECB pin-out guide (as per photos). This can be then be glued to the side of your DIN41612 connector, for a very handy adjacent reference to the 64 pin header for bus signal access!

Prototype PLD Card BOM

The following is a full Bill Of Materials (BOM) to allow fully assembling your Prototype PLD Card.

Note that the PCB is supplied, and all components are available via the two option packs.

Some components are of course optional. For example, you may not want the PLD to get started. Also, you may choose to just use a regular IC Sockets. I do highly recommend an IC Socket is used as it is likely you will eventually want to re-program your PLD.

I have also included an indication of where I sourced my parts from, if this is of assistance.

Via the Documentation link (below) you'll also find related videos, and other videos presenting different components of the MECB retro 8-bit computing project.

Your Prototype PLD Card Kitset order is shipped in a robust cardboard carton with packing, for safe delivery via New Zealand International Air Parcel (see example shipping photo).

Note: Visit the Documentation link (below) for more information on MECB, and for details of the various MECB Cards that have been design so far.