Darmstadt electronic calculator
The Darmstadt Electronic Calculator ( DERA ) was an experimental room-sized electronic computer with radio tubes built from 1951 . It was built at the Institute for Practical Mathematics at the TH Darmstadt under the direction of Alwin Walther . The “computer” was accessible for repair purposes behind the walls with the radio tubes arranged horizontally there (see picture in).
Technical specifications
- Start of construction 1950/51, start of use in 1957, completion in 1959 (not ready for series production as it has been overtaken by transistor technology).
- Programming languages: in addition to machine code, ALGOL .
- I / O device: teleprinter (paper tape reader).
- Word machine with Stibitz code (also excess -3 code), 20 bit (13 decimal places + sign )
- Command length 7 digits
- Magnetic drum memory with 3000 words
- Ferrite core register (20 ms access time)
- Clock frequency 200 kHz (addition 0.8 ms; multiplication 12 - 16 ms)
- Components: 1,400 tubes, 8,000 diodes, 90 relays
Web links
- Archive of Darmstadt University of Applied Sciences: Picture front view DERA and further information
- Archive Uni Erlangen: Picture control of magnetic drum storage
- Archive Uni Erlangen: picture adding circuit
- Archive Uni Erlangen: picture plug-in unit
Individual evidence
- ^ Rainer Bischoff: On the history of computing technology and data processing ( Memento of the original from April 21, 2008 in the Internet Archive ) Info: The archive link was automatically inserted and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Alwin Walther - Pioneer of Practical Mathematics, there Fig. 2 (PDF; 1.9 MB)
- ↑ Wilfried de Beauclair: Calculating with machines: a pictorial history of computing technology. Jumper; 2nd ed. Edition (March 29, 2005) ISBN 3540241795 p. 148. [1]
