Need assistance with a hardware development project

Expert (116)

05-01-2012, 09:01

Hi everyone, it's been a while since my last post, but life has been super busy. Anyway, I need some help with a simple hardware project. I've just bought an FM-77 AV 40 SX, but I got it without a keyboard. I have all the information required to create an adapter to let me use PS/2 keyboards with the FM, but I just don't have the practical hardware development experience to turn the information into an actual device. Can someone give me a little help? I have all the codes that the keyboard sends to the computer for every single key, as well as the data rate, the repeat timing, and how the keyboard responds to multiple keypresses, as well as the pinouts. I know this problem can be solved with a uController or a (C)PLD but I just don't have the experience with VHDL or Microcontrollers nor the knowledge of the PS/2 protocol to actually put it together. Can someone possibly help me? I will post all the pertinant information below:

Info on data rate etc: https://docs.google.com/document/d/1ES069x3zrfYlR6ruTYY5UFvNByLysXoxOFGJ-IDGm4A/edit
Keyboard Serial Codes: https://docs.google.com/spreadsheet/ccc?key=0Alhvp8gopwkpdG03Ni10UmNrN2tzQ2U4TWlTUHFnVnc
Pinout: https://docs.google.com/open?id=0B1hvp8gopwkpOGQ5NjM0ZGYtNWI0My00NzM5LThmNzEtOGUwODY0MmQ3NDM2

I know there are more then a few people with FM 77 AV series machines looking for keyboards, so this could actually make back anything anyone puts into it. I am capable of assembling any boards (if they are through-hole that would be even easier ;)) I just need help with the design side of things. Please, if anyone out there can help me, it would be very much appreciated. I can't put the FM 77 AV in my museum without a keyboard.

By caro

Champion (512)

05-01-2012, 10:32

It would be good to look at a picture package with the timing of the pulses.

By caro

Champion (512)

05-01-2012, 14:36

Look subject to: http://www.vintage-computer.com/vcforum/showthread.php?15907...
Here we are talking about converting code from AT Keyboard (PS/2) to XT standard.
In the subject is a diagram of a converter based on the 8 pin PIC controller PIC12F629 (or PIC12F675).
and the source code of the software.
Scheme without altering a widely can be used to solve your problem.
Sources can help you to write a program code conversion PS/2 keyboard to 40-bit code used
in the interface of your keyboard.

By TheRogue

Expert (116)

05-01-2012, 19:14

Hey Caro, thanks so much for replying so quickly. I wish I could give you a picture of the timing of the pulses, but without owning a keyboard myself I can't. I might be able to build a simple Arduino oscilloscope and send it to someone I know who does have an FM77AV keyboard so they can sample the feed, but that won't be possible for a little while. I actually just had an idea! Wouldn't it be possible to do this on an Arduino? That would eliminate the need to build a project! Does anyone have Arduino experience?

By WORP3

Paladin (855)

05-01-2012, 20:06

A good starting point in understanding the ps2 keyboard is the fllowing site:

http://retired.beyondlogic.org/keyboard/keybrd.htm

By Manuel

Ascended (18719)

05-01-2012, 21:48

Ok, so what is an FM-77 AV 40 SX?

By TheRogue

Expert (116)

06-01-2012, 00:24

Thanks WORP3, I'll check that out when I get home from work. Manuel, an FM-77 AV 40 SX was the very last 8 bit machine Fujitsu made before they moved on to the FM Towns 32 bit machines that everyone knows. Many people claim it is the ultimate 8 bit machine, at least those who know about it do. It is very rare. It is a dual 6809 based system. It is the last in the FM-7 series of machines that started out somewhat like the CoCo. It has incredible AV features, such as 320x200 in 262144 colors, the ability to overlay computer output onto TV signals, high quality audio, and so on. It's quite common to find them for sale without a keyboard, and keyboards by themself for sale are rare in Japan and unheard of elsewhere. This is why I want to solve this problem. Not just for me, but for everyone else who has one without a keyboard.

By WORP3

Paladin (855)

06-01-2012, 09:20

I guess if you really want to make a converter, a simple micro controller will be the easiest way !
The 6809, still give me good vibes Very nice processor which has very good stack handling !

By Sander

Founder (1867)

06-01-2012, 09:30

What has this to do with msx development?

By Jorito

Mr. Ambassadors (1782)

06-01-2012, 10:11

Moved topic to semi MSX talk.

By TheRogue

Expert (116)

08-01-2012, 05:44

Just to let everyone know, someone from another forum has agreed to take on the problem. They are going to modify a board they designed for converting ADB to PS/2 to suit my needs since the FM-77AV40SX uses the same connector for keyboard data as the Mac used for ADB. I will keep everyone posted on the details.