Thoughts on the µPF--2 Z80 kit dev board.

 

In fact, when I look at the system I built, even though I did it based on compatibility with the original µPF--1 kit at the time, I realize that my version looks more like a microcomputer than a development board.

https://collection.onceuponabyte.org/ident/COMP-0156

At the time, when I studied with this machine, in 1987 I think, the PC was not yet very widespread. There was no adequate development software and furthermore the µPF - 1 did not even allow program loading through a communication port.

It was therefore necessary to provide all the hardware and software functions to allow the entry of mnemonics in assemblers, live editing and correction, memory modification, program launch etc etc ...

As my kit works, in fact I realize that I am exclusively using the C language, a PC text editor, and the SDCC compiler. Then, once the program is completed, I download it directly into the µPF - 2 and start the execution. I absolutely do not use the basic functions of the system.

So I made the decision to convert this set into a modern Arduino style development system but still keep the 'retro' side thanks to the Z80 hardware emulation. The entire development process will take place through the serial port via the standard tools available for PC.

The objective is to be able to train easily and in a fun way, not only in programming, but also in interaction with the outside world and finally that real applications can be managed by this system.

Multitech IOM board

I am therefore going to develop a first interface board like the IOM original board which will allow the µPF - 2 to be autonomous, capable of loading its application program itself, launching it and of interacting with the outside world in the manner of an automat. 

Do not hesitate to send me your comments.

Best to you.

Back to the 90s

At the time, I saw this kind of covers on certain magazines. There was something other than the extreme and boring standardization of Apple and Microsoft. 30 years of crossing the desert! A new start, I hope, for other things more eclectic and more interesting...

A SMALL MIDI TOOL (next)

Another problem that really annoys me when I want to quickly jump to a patch on a specific synth. is that it is never easy. You have to go to the PC to play with the mouse, or type on the series of control keys of a particular hardware sequencer. Or more simply, get up from your seat to change the patch directly on the machine.

I decided to create a small simple module allowing to select a MIDI channel as well as a change of patch on the selected channel.

Here is the result of my thoughts on the subject:

Unlike the Midi Merge Box project, here, the system must fit into the MIDI chain. The system cannot therefore be passive and must insert the patch change commands only when the MIDI 'network' is available.

The second challenge consists in power the Patch selector from the MIDI bus. Indeed, such a device which must be inserted in a MIDI chain can be very quickly painful to use if in addition it is necessary to manage the power supply unit.

To do that, it is necessary to develop a system whose power consumption remains below 20mA, ideally below 15mA. this time, I chose a microcontroller that I haven't used for over 15 years but which turns out to be very energy efficient and above all very easy to program / debug.

At the stage where I am developing my little studio, I have now to decide for a mixing console. I would go for a RACK version because I don't have a lot of room in my studio!

What do you think of Yamaha's TF-R rack console?

Tell me if you have any comments on this console ...