Less than 1 -bit architecture is understood in the computer systems, which only use 1 bit in a work cycle. An example of a true 1 -bit architecture, which was actually produced as CPU and marketed, the MC14500 Industrial Control Unit from Motorola. In addition, there are several academic design studies for 1 -bit architectures, and the logical model is reflected in the programming, which is compiled on different target hardware.
Typical representatives of the 1 -bit architecture, the so-called programmable logic controllers ( PLC). The term is primarily indicative of the used programming language on the system, for example, Instruction List (IL ), but says generally nothing about the underlying processor platform. These may be strong deviation from parallelism, optimization and conversion in hardware to solve the PLC program task 1 bit. For example, an STL program with 1- bit logic with an STL compiler into machine code for a 32 -bit processor (32 -bit architecture ) to be translated.
Typical program for a 1 -bit architecture:
- Loading the digital input 1 in the 1- bit register
- ( OR ) linking the value in the 1 -bit register with input 2, the result remains in register
- Write the value in the 1 -bit register to output 1
The limitation of the programming model to 1 bit allows a control task with the least possible number of required process elements is implemented in a program. For products with quantities as low as one will fall back on a general purpose processor from another area ( for example, from the 4- bit or 8 -bit architecture ), at high volumes, the execution as a special chip ( application specific integrated circuit ) is possible at each program step to be 1 -bit oriented transistor group is expressed with conductor tracks. The cheaper FPGAs allow to be produced that are highly linguistically written programs to be implemented in a configuration file with the one -bit function elements are interconnected dynamically on these chips, which then correspond to a hard-wired logic in operation.