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Latest toys arrived today: A slew of modules for the 8085 powered "Microcomputer für Ausbildung" by the vocational training centre "Berufsförderungszentrum Essen".



The trainees often bought kits and built it from scratch, etching, soldering and doing the metalwork.

It's using an ECB style bus connector with a passive packplane in a 19" rack, but I haven't checked yet if the lines match ECB per se.



The modules pictured are just a part of what used to be available, originally all well documented and accompanied by training material.

Hardware could often be mixed and matched depending on the task at hand (trainees learned basic computer operation as well as assembly programming and the operation of industry automation systems).

Just as new modules could be added, the software was modular as well: the most basic monitor program is called MAT85 which fits in 8K of ROM, additional software including a business BASIC, automation simulation and others brought it up to MAT85+ (16K), add an editor and floppy routines you get MAT32K (32K, duh). All simpler stages of the software were still present in the ROM once you got up to MAT32K.
Several modules already had the provisions to make the MFA capable of running CP/M given the proper ROM.



In this screenshot, KMD (Kommando) is the MAT85 prompt, KMD+ stands for MAT85K

Part of the documentation is available here:

ftp://ftp.informatik.uni-stuttgart.de/pub/cm/mfa8085/MFA.pdf

There was even an emulator of the MFA for the Amiga:

http://ftp.fau.de/aminet/misc/emu/MFA-Simulator.lha

The ROM that is contained is the 16K MAT85K, but it's concatenated from its original 8x2K.

My computer has the MAT32K ROM.

https://mega.nz/#!2Qx32QDZ!g8fVOm0GPR3K0ZPv7sT4FpXWcDjN97_8NsKcx_Fdt0M

The regular video interface (not suitable for CP/M) creates a terminal connected to the SID and SOD pins of the 8085. It takes its input from a parallel ASCII keyboard and outputs video to a regular composite monitor. The chips involved are a AY-5-1013A UART the 2513 character generator known from the Apple I and a EF9364AP graphics chip.

The archive linked above contains a dump of the ROM of the more advanced CP/M capable video interface.

I will post pictures and schematics of the other modules as I get round to scanning/photographing them. So far I've got the ones on the first picture plus parallel input, AD/DA, programmable serial and, for lack of a better word a "poke" module that compliments the one with the LED display - you can use it to inject hex values at certain memory addresses using switches.

Which mask of the 2513? There were several made, the original apple1 uses a 'common' one (2513-COM?) but afaik the apple2 versions had a few custom characters?

LN

Hi LN, the part is marked R03-2513 CGR0001

https://mega.nz/#!DAREjQTY!qT4J8xV6o7YUgqpmyHvqOHomvqcQFvC_V_XOBbNruDs

I'll clean up this scan later, but for now you can find the characters of the 2513 on page 6 of the PDF. My Eprom reader doesn't support the part.

Here are photos of the module:

https://mega.nz/#!nJZ1nCLT!ooOS2CLUj2iDnR-hIdr5KKS1nr7oIkDwx8n80C9jYH0

Cool, what kind of bus is it?

I like CNC:s as you know, is there such a rom/software for it?

Edstrom, if you look at p38 of mfa.pdf in the second post, you'll find the bus pinout.

I don't know yet what software officially existed, but I've seen problems the students were asked to solve - like automated traffic lights and similar.

Ahh, interesting pin numbering with address and data bus alternating between row A and C. Either it is a very bare bones bus with only memory R/W and I/O R/W on top of that or there are more signals for interrupts and arbitration, there probably must be.

I have been thinking about a student lab slot device for my didact/esselte driver, where each lab gets a set of additional hardware and a unique layout but there are a few milestones to get there which I also need for the VME drivers:

- sub-layouts which can be rendered in run-time by the board driver from an offset within the main layout. For slot device front panels and other visible add-ons
- animations where you step through a number of bezels. To show motor spins, small robot movements and static graphics.
- setting offset to a sub-layout so it can move within a layout for hot-swap of slot devices, elevator labs, bigger robot movements, etc

However I am not into the layout engine atm so I can't add that myself.

Alternatively this can be done in Lua but there I think we need to set a standard for slot device graphics and how to make them co-exist. I am not on top of such a solution either.

Nice! There are some signals that could be daisy chained like the RSTIN and RSTOUT respectivelly. If daisy chained these are not connected directly RSTIN to RSTIN pin but rather RSTOUT to RSTIN so that each card can jumper or delay/block the signal.

This is only an educational bus which is evident from seeing Rx and TX. If these are multi drop there is a challenge emulating those in MAME I think.

Other than that I think the best way is to run some software in MAME in parallel with the system and see how far they are doing the same thing

The description of any self respecting computer system starts with its CPU, doesn't it? Well, in this case the bus indicator and bus signaller modules are somewhat iconic for the MFA system, and the documentation describes several tutorials that don't use the CPU module at all.



This pair of modules can be used to teach the interaction between address, data and command signals, debug modules, find out the memory map etc.


MFA Bus signaller 5.1B.zip


MFA Bus indicator 5.2B.zip

The archives contain the relevant chapters of the manual and photos of the modules.

Next is the 8085 CPU module.



It's got a handy reset switch in the front panel and has the solder pads to connect a V24/TTY interface (cf. p.273ff of MFA.pdf posted earlier).

MFA CPU 8085 2.1B

The oscillator next to the CPU is a 4MHz part.