website/content/museum/motorola-wdr-1-bit-computer.md

title, categories, types, origins, years, cpus, params

title	categories	types	origins	years	cpus	params
Motorola WDR-1-Bit Computer	Computers	Home Computer	U.S.A.	1981	Motorola MC-14500	name image company company_name specs tabs forum_thread photos links oc_id source WDR-1-Bit Computer /media/museum/photos/motorola_mc14500_system_1.jpg /companies/motorola Motorola label value NAME WDR-1-Bit Computer label value MANUFACTURER Motorola label value TYPE Home Computer label value ORIGIN U.S.A. label value YEAR 1981 label value END OF PRODUCTION 1990 label value BUILT IN LANGUAGE None label value KEYBOARD 29 keys with instruction and octal keypads, Reset and clock keys label value CPU Motorola MC-14500 label value SPEED From manual clock pulses to 1 MHz label value RAM 256 byte to unlimited memory size label value ROM Unknown label value TEXT MODES LED display label value SOUND Sound capabilities label value BUILT IN MEDIA none label value POWER SUPPLY 9V battery label value PERIPHERALS Unknown label value PRICE 135 photos links 815 title subtitle text image SYSTEM BOARDS /media/museum/photos/motorola_mc14500_system_2.jpg title subtitle text image KEYBOARD CLOSE-UP Notice the 16 white keys, one for each processor instruction, and the black octal numeric keypad. Processor instructions set:\ **NOP** No Operation\ **LD** Load result register\ **LDC** Load complement\ **AND** Logical AND\ **ANDC** Logical AND complement\ **OR** Logical OR\ **ORC** Logical OR complement\ **XNOR** Exclusive NOR\ **STO** Store\ **STOC** Store complement\ **IEN** Input enable\ **OEN** Output enable\ **JMP** Jump\ **RTN** Return\ **SKZ** RR = 0\ **NOPF** No Operation, set flag /media/museum/photos/motorola_mc14500_keyboard_1.jpg title url text German page about the WDR computer http://www.wdr-1-bit-computer.talentraspel.de Including the full WDR user manual (in German). 834 url date https://web.archive.org/web/20230528105009/http://www.old-computers.com/museum/computer.asp?c=834 2023-05-28

This is a homemade and nicely built training computer, and probably one of the rare computers in the world based on the 1-bit (yes, one bit) Motorola MC14500 processor.

This machine was conceived en sold in Germany by DATANorf Hard and Software in kit or ready-built forms.

Originally, the MC-14500, also called Industrial Control Unit (ICU) was a CMOS processor designed for controlling simple industrial devices and making binary decisions based on successive single bit information. One could find it also in LCD display drivers or as a serial port manager.

It has 16 instructions, including bit transfer, logical single bit comparisons (OR, XOR, AND, NAND), Jump and subroutines. Its internal clock speed started from manual pulses to about 1 MHz.

The pictured computer, made by a German anthusiast, worked when connected to a 9V battery. It includes a LED IO board, CPU board and 512 byte RAM board. The keyboard featured one key for each processor instruction and an octal numeric keypad. Some sounds may be produced through the attached amplifier and loudspeaker.

More information from Kai Ludwig:
The MC-14500 based "WDR-1-Bit-Computer" was invented about 20 years ago as a holiday-project by Burkhard John and Volker Ludwig for educational purposes.

In those days I was running the german company "DATANorf Hard and Software". It sold the "WDR-1-Bit-Computer" as kit. The ciruitboards were homebrew and there were many additional modules available.
Later we made an 6 part educational school-TV-serial with WDR Television and the German company Raffel-Electronics got the licence for professional distibution of the kits with industrial manufactured circuitboards.

Your picture shows a version sold by DataNorf to a home enthusiast. The attached board contains a NE555 oscillator to make a sound. The pitch can be adjusted by the potentiometer.

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.