website/content/museum/tesla-pmi-80.md

title, categories, types, origins, cpus, params

title	categories	types	origins	cpus	params
Tesla PMI-80	Computers	Home Computer	Czechoslovakia	TESLA MHB 8080	name image logo company company_name specs tabs photos adverts connectors comments oc_id source PMI-80 /media/museum/photos/tesla_pmi80_system_s2.jpg /media/museum/logos/tesla_pmi80_logo1.gif /companies/tesla Tesla label value NAME PMI-80 label value MANUFACTURER Tesla label value TYPE Home Computer label value ORIGIN Czechoslovakia label value BUILT IN LANGUAGE Machine language hexadecimal monitor label value KEYBOARD 25 key calculator type - Hexadecimal and function keys label value CPU TESLA MHB 8080 (Intel 8080 clone) label value SPEED 1 MHz label value CO-PROCESSOR None label value RAM 1 KB label value ROM 1 KB label value TEXT MODES 9 digit, 7 segment, diode calculator type label value I/O PORTS DIN 5-pin Power - DIN 5-pin analog I/O to tape - label value POWER SUPPLY External power supply unit, +5V / -5V / +12V label value PERIPHERALS Additional ROM and I/O chip sockets photos adverts connectors title subtitle text image MAIN BOARD **(1)** Tape recorder DIN socket\ **(2)** MHB 8080 microprocessor\ **(3)** MH 8228 (Intel 8228 clone) - MicroBus controler, converts CPU signals into I/O, MEM, R/W signals\ **(4)** MHB 8255 (Intel 8255 clone) - main I/O chip, 3x8-bit I/O channels, 1 channel for user, 2 channels for keyboard & display\ **(5)** Second optional 8255 offering three additional I/O channels\ **(6)** ROM chip holding the MONITOR program\ **(7)**MH 8224 clock generator and MH 3205 memory controller\ **(8)** Two MHB 2114 (Intel 1k * 4-bit 2114 clone) RAM chips holding the 1 KB user RAM\ **(9)** Optional I/O card connectors An expansion bus is also located between the microprocessor and the ROM chip. /media/museum/photos/tesla_pmi80_system_s1.jpg title subtitle text image COMPLETE SYSTEM Thanks to **Horymir Marek** /media/museum/photos/tesla_pmi80_system_s3.jpg title subtitle text image PMI-80 CASE /media/museum/photos/tesla_pmi80_case_s1.jpg title subtitle text image CHIPS CLOSE-UP CPU, I/O, ROM and RAM chips. Thanks to **Horymir Marek** /media/museum/photos/tesla_pmi80_boardcloseup_s2.jpg title subtitle text image KEYBOARD /media/museum/photos/tesla_pmi80_keyboard_s1.jpg title subtitle text image DISPLAY Calculator type diodes display /media/museum/photos/tesla_pmi80_display_s1.jpg title subtitle text image DISPLAY #2 When the computer starts, it displays this message. Thanks to **Horymir Marek** /media/museum/photos/tesla_pmi80_displight_s1.jpg title subtitle text image PMI-80 LOGO null title subtitle text image I/O CARD This card displays each bit of the data bus. It also has a digital to analog converter which allow 0V to 12V output with 256 steps. The max voltage can be adjusted, between 0 and 12V, thanks to the variable resistor. /media/museum/photos/tesla_pmi80_iocard_s1.jpg title subtitle text image MANUALS The manuals were actualy a complete course on each chip which make up the computer. Thanks to **Horymir Marek** /media/museum/photos/tesla_pmi80_manuals_s1.jpg title subtitle text image DIAGRAMS PMI-80 diagram located in the case cover.\ If you are interested in more diagrams of the PMI-80, dowload this zipped file holding three diagrams of the whole system. /media/museum/pubs/tesla_pmi80_casecover_s1.jpg title subtitle text image CHIPS ARRANGEMENT Thanks to **Horymir Marek** /media/museum/connectors/tesla_pmi80_diagram_s1.jpg title subtitle text image CPU Thanks to **Horymir Marek** /media/museum/connectors/tesla_pmi80_diagram_s2.jpg title subtitle text image CONNECTORS Thanks to **Horymir Marek** /media/museum/connectors/tesla_pmi80_diagram_s3.jpg title subtitle text image KEYBOARD, TAPE INTERFACE & POWER REGULATION Thanks to **Horymir Marek** /media/museum/connectors/tesla_pmi80_diagram_s4.jpg author date text Nyxt Tuesday 8th March 2022 this is basic author date text Nyxt Tuesday 8th March 2022 Did you lose you mind, Elon Musk? author date text belgium4 (Belgium) Monday 12th September 2011 I have one in my collection.\ I''m glad that I''ve found some info aroung this single board computer.\ Thnx\ Michel author date text Roman Kiss (Slovakia) Sunday 10th June 2007 Thanks for remember me this baby. It was a long time ago, in the big garage Tesla. author date text Gergely Takacs (Slovakia) Wednesday 18th May 2005 Yes there is an emulator for PMI80... Altough I've heard there are some problems with it under W.XP, I can work with itt allright. The interface is pretty darn simple (just as probably the PMI80 was)... author date text Linkman (Slovak Republic) Saturday 23rd April 2005 Is extra emlator for PMI-80? author date text Blackhead (Prague) Tuesday 25th May 2004 If you want to know enything about it ask here. I'll answer it! 1016 url date https://web.archive.org/web/20230606190802/http://www.old-computers.com/museum/computer.asp?c=1016 2023-06-06

The PMI was used for learning programing machine code in Czech and Slovakian polytechnic university from 1982 year.

It was developed and manufactured in Tesla Piestany factory which core business was to produceo active components like diode, transistor and integrated ciruits, including the MHB 8080A CPU and chip from his family.

It was a basic system, enclosed in a plastic case and precisely based on the MHB 8080A, a Tesla version the 8080 processor.

It had minimal ROM, RAM and I/O capabilities, but enough in schools, to enter, study and run small programs.

Thanks to Jiri Cernohlavek, from Czech Republic, for information and pictures.

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Martin Bruno remembers:
I used this computer when I was attending Industrial College Of Electrical Engineering in Eastern Slovakia, town of Michalovce at second class in 1994/95 and this computer was widely used at Slovakian technical schools for learning machine code of 8080 processor.
It was a bit complicated because you had to write program in hex form. Actually it was computer but practically not for home use nor for some entertainment... it was a good form how to scare people about machine code programming :-)
I must to thank my home computer Didaktik M at that time that I learned machine code resp. assembler in much more comfortable way :-)

Dan Handenberg adds:
The computer was originally designed to control printing machines, but the processing was too slow to transfer information fast enough to the peripherals.

We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.