PDP-14


The PDP-14 was a specialized computer from Digital Equipment Corporation. Unlike DEC's general-purpose computers, which are simply called computers, this unit had no data memory or data registers and was intended as an industrial controller a programmable logic controller.
Its instructions can test Boolean input signals, set or clear Boolean output signals, jump conditional or unconditionally, or call a subroutine.
I/O is line voltage.
Later versions are based on PDP-8 physical packaging technology. There also was a PDP-14/35 and a lower cost/reduced I/O capability PDP-14/L.

Hardware

The 12-bit PDP-14 could hold a maximum of 4K words for instructions. The system's configuration included a control unit and a number of external boxes:
Hence the combined usable output address space of the O-boxes, A-boxes and S-boxes was 255 or fewer.

Registers

The PDP-14 has seven 12-bit registers:
Among the PDP-14 instructions were:
In effect, JMR is actually a specific TRR in which PC2 is transferred to PC1.
There were also TEST instructions and SET instructions.

Software

The original PDP-14 required that programming be done by DEC.
Subsequently, software development for the PDP-14 was done on another system, the PDP-8. A PDP-8
program named SIM-14 allowed for simulating the PDP-14.

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