Note: The 6309 CPU PLCC Card is supplied in Kitset form only (assembly required). The base price is for the double-sided silkscreened 6309 CPU PLCC Card PCB ONLY. The optional packs provide some key components only. Other components are also required to make a complete 6309 CPU PLCC Card Kitset. See BOM below (and photo).

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) 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.

6309 CPU PLCC Card

The "6309 CPU PLCC Card" is a follow-up to the original 6809 CPU Card and the 1MB ROM Expansion Card (both still available).

This new Card takes advantage of the smaller PLCC package size for the CPU and ROM, to enable combining the functionality of these two previous Cards into an attractive PLCC based design.

I like PLCC packages, as they're not only attractive to look at, they're also satisfying to insert into a PLCC socket! The PLCC sockets are also available in the Retro friendly Through-Hole (TH) format, which I've used here.

I've also chosen the HD63C09 CPU variant, to provide the fastest manufacturer rated clock speed for a 6809 compliant CPU Card (3MHz), and I've also used fast 15ns SRAM and 70ns FLASH ROM to allow faster over-clocking! As such, my initial testing of the new Card was with a 16MHz oscillator (4MHz CPU speed). Of course, over-clocking is not recommended, so if you want to replicate this (or go even higher), please remember you do risk damage by exceeding manufacturer ratings.

Due to all the above, this is my current favourite MECB CPU Card!

What You Get

To satisfy different people's needs, I've split the 6309 CPU PLCC Card Kitset into optional add-on packs.

Firstly, note that the base price is for the double-sided silkscreened 6309 CPU PLCC Card PCB Only.

Then, you can add the optional Packs that might be helpful to you. Then, to complete the Kitset, you'll need to source the remaining parts to complete the BOM below.

I've tried to account for all of the more specialised parts (and convenience) in the optional packs, with the thought that the remaining items are likely already in your hobbiest parts drawers (or quite easily obtainable).

Please view the second photo, for a visual representation of the available option packs.

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)
• 4x 12mm Nylon PCB Spacer
• 8x 6mm Nylon Bolt (for Spacer mounting)

Optional Programmed ATF16V8 PLD Pack includes:

• 1x ATF16V8 PLD Chip Tested and Programmed for the 48K RAM + 16K ROM memory map (as required by the Programmed SST39SF040 FLASH ROM optional pack).

Optional Rotary Coded Switch Pack includes:

• My researched good quality 3:3 footprint 16-Position Rotary Coded Switch.

Optional Programmed SST39SF040 PLCC32 FLASH ROM + PLCC32 Socket Pack includes:

• 1x SST39SF040 PLCC32 packaged 512KB FLASH ROM Programmed with the ASSIST09 monitor in Bank 0, and 6809 Extended Basic in Bank 1 (i.e. The same as the 1MB ROM Expansion Card).
• 1x PLCC32 Through-Hole (TH) IC Socket for the above.

Optional Blank SST39SF040 PLCC32 FLASH ROM + PLCC32 Socket Pack includes:

• 1x SST39SF040 PLCC32 packaged 512KB FLASH ROM which is blank, ready for you to program with your desired content. This could also be your second ROM (ROM1), if combined with the Programmed ROM option above.
• 1x PLCC32 Through-Hole (TH) IC Socket for the above.

Optional Tested HD63C09ECP PLCC44 CPU + PLCC44 Socket Pack includes:

• 1x HD63C09ECP 3MHz rated PLCC packaged Microprocessor (Tested & Verified)
• 1x PLCC44 Through-Hole (TH) IC Socket for the above.

6309 CPU PLCC Card BOM

The following is a full Bill Of Materials (BOM) to allow fully assembling your 6309 CPU PLCC Card.

Note that the PCB is supplied, and some select components are available in the option packs. The rest of the more general components will need to be sourced by yourself (if not already in your parts drawers).

Some components are of course optional. For example the DIL IC Sockets, although I do highly recommend IC Sockets are used throughout.

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 more information on the MECB system and other available Cards, as well as videos presenting different components of the MECB retro 8-bit computing project.

Your 6309 CPU PLCC 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: Please visit the Documentation link (below) for more information on MECB, and for details of the various MECB Cards that have been design so far.