Phywe instructional computer
UvA Computer Museum catalogue nr 01.44
In the memory unit (left of the middle in the upper picture), each bit storage cell is implemented by a capacitor. The computer uses electromagnetic relays for all of its gates. These relays are clearly visible as the rectangular boxes in the lower picture, showing part of the inside of the machine (the control unit).
The system clock runs at about 3 steps per second; a program can also be stepped through manually. A lot of small incandescant lamps show what is happening.
Programs are entered by means of a set of 6 push buttons (lower middle part of the panel).
The machine, which is complete and in working (*) condition, was designed and built (in a series of 30 **) by the PHYWE company of Göttingen, (at the time Western) Germany, which still exists as a provider of training systems in natural science and technology.
This computer was donated by Mr. L. van Stratum, Eindhoven, The Netherlands.
*) Movie file phywe.avi, size 4 MB, shows the execution of a three-instuction program. The first two instructions are identical (001 101), each adding the contents (12d) of memory address 5d to the accumulator (lower right). The third instruction is 000 000 'stop'.
The lamps to the extreme left correspond to the instruction set: the lower lamp lights if STO(P), instruction 000 is decoded; the next one corresponds to ADD(IEREN), instruction 001. More instructions are not used in this example.
**) This piece of information was provided by Jens Kirchhoff, Göttingen.
