The Micro-Professor MPF-1 is a training system designed to teach the fundamentals of machine code and assembly language for the Zilog Z80 microprocessor. A training system was typically used by students within computer science or by designers that wanted to design a computer around a specific microprocessor.
The MPF-1 is known as a Single Board Computer because all the components like, CPU, RAM, ROM, I/O etc. is located on the same printed circuit board.
The ROM on this B version is loaded with a BASIC interpreter and a simple monitor program. A program could be entered through the keyboard or loaded through the audio interface connected to a cassette player.
This embedded system is an early predecessor to todays Arduino and Raspberry Pi embedded computers. The biggest difference is that all the functionality is merged into a single chip instead of dedicated hardware for CPU, RAM, ROM, I/O etc.
The MPF-1 is an iconic Z80 based development board among the earliest single board computers only beaten by based 8080 Intel SDK-80 1975, 6502 based KIM-1 1976 MC68000 Educational Computer 1981.
It’s a funny little computer in a box with integrated display and keyboard.
This computer is relevant because it shows the basic element of a computer and is an early predecessor to embedded controllers like Arduino, Raspberry Pi or similar.
|Form factor||Single Board Computer for training|
|CPU||1.79 MHz Zilog Z80|
|RAM||2 kB (upgraded to 4 kB)|
|Storage||Interface for cassette drive|
|Display||6 digit 7-segment LED display|
|OS||No OS just pure machine code in hexadecimal format|
However the B version includes BASIC and Monitor in ROM
|Dimensions||157 x 223 x 25 mm|
|Weight||295 g (613 g incl. box )|
|I/O ports||Z80 CPU BUS, PIO CTC I/O BUS, Ear+Mic for cassette interface,|
|Power||DC 9 V, 0.6 A plug|
|Special features||Computer, display, keyboard and speaker on the same PCB. Comes in a book format enclosure.|
|Successor||MPF-1P which have a larger VFD display and a QWERTY keyboard|
|Condition||The enclosure is in bad condition, front and back has almost come apart. The computer itself is in good condition without sign of wear. Does power up with light in the display but further testing has not been done.|
|Accessories||Enclosure, BASIC keyboard overlay and display format sticker|
|To do||Try to play around with some BASIC programming|
I bought this computer on DBA for a good price. I’m not sure the seller even knew what he sold me. When I got it, I was surprised to see that it was the updated B version with BASIC in ROM. A couple of years before I bought this one I saw another seller who sold both the MPF-1 and the MPF-1P (plus) for a price, which I back then thought was a little high, but now I’m annoyed that I didn’t got them. Because the MPF-1P is hard to get and very expensive on eBay.
Restoration and modification
I installed another AM9128 RAM chip to double the amount of RAM to 4 kB in total. Actually it was just to have the board fully populated rather than because I needed the extra RAM.