RC2014 Modular Computing

A first glance at the RC2014 full Monty kit

The RC2014 is an 8-bit Z80 based modular computer with support for running Microsoft BASIC. The 'Full Monty' Kit is what I decided I would go with and this contains a full set of modules which are required to get a working computer.

The thing that is really cool about this kit is that it takes you back to the very basics by building essentially what is a 1980's micro-computer.

When I first received the kit there were practically no instructions on how to assemble this available online. So to begin with I could see how this could be quite daunting for anyone who doesn’t really understand how a computer such as this works. Since I began, assembly guides for each module including the schematic have been published, which make it easier to understand how everything works together. I like to think of this kit as a six jigsaws with all the pieces mixed together in one box, some pieces are obvious and others aren't – but you can refer to the BOM and schematic for each board if in doubt.

Modular Computing

The kit comes with a standard set of six modules which I need in order to get the computer working. These are:

• CPU: Z80
• ROM: 27C512 64 KB ROM, selectable in 8KB banks. Theoretically this allows you to have 8 different programs, selectable by jumper and available to boot.
• RAM: 62256 32 KB
• Clock: 7.3728 MHz crystal (This drives a 74HC04 hex inverter and also the Z80 and the UART on the serial board)
• Serial I/O: MC68B50 UART (can be directly connected to a FTDI cable, or can populate the MAX232 socket for a real 9-pin serial port)

Image Source: http://rc2014.co.uk/blockdiagram/

In addition to these modules I also purchased the universal micro keyboard so I could interface with the computer while keeping the retro feel. To first get started I separated the pieces into bags the best I could – note although I am not assembling anything in this post I feel it is easier to look at each module in more detail once all the pieces for each are together.

What really appealed to me about building a retro Z80 computer from scratch was that it’s incredibly educational! Having individual modules means that each one can be looked at in closer detail, which is great, especially for someone like myself who learns better from a hands-on approach instead of the textbook method.

Expansion Boards

One of the expansion boards which you can buy for the kit is the Digital I/O board and with this it enables you to interface with the Z80 just like you would be able to an Arduino. Once I have finished building all the modules and have managed to get the computer working, I would like to purchase this so then I can see how you can use a very basic computer for control.

Programming

One of the languages which the RC2014 supports for programming is Microsoft BASIC. This is a major implementation of the BASIC language, which is an abbreviation for Beginners All-purpose Symbolic Instruction Code. BASIC is a family of general purpose, high-level programming languages which emphasises ease of use in it’s design philosophy.

BASIC was in widespread use with microcomputers in the mid-1970’s and 1980’s – at a time when use of computers often required writing custom software – the idea was to enable students in areas other than science and maths to use computers. This is another reason why I’m really excited to use the RC2014, because all round it is a fantastic platform to start out on for anyone who doesn’t know much about computers, with respect to either hardware or software. If you really wanted to go back to the bare basics when programming the RC2014 you can even use Z80 machine code.

To read more about this visit the RC2014 Github Repo.

Part II

In the next post I will run through assembling the modules as well as more about what each module does and finally testing the RC2014.