Aserial computer is a computer typified bybit-serial architecture – i.e., internally operating on onebit ordigit for eachclock cycle. Machines with serialmain storage devices such as acoustic ormagnetostrictivedelay lines androtating magnetic devices were usually serial computers.
Serial computers require much less hardware than their bit-parallel counterparts[1] which exploitbit-level parallelism to do more computation per clock cycle. There are modern variants of the serial computer available as asoft microprocessor[2] which can serve niche purposes where the size of the CPU is the main constraint.
The first computer that was not serial and used aparallel bus was theWhirlwind in 1951.
A serial computer is not necessarily the same as a computer with a1-bit architecture, which is a subset of the serial computer class. 1-bit computer instructions operate on data consisting of single bits, whereas a serial computer can operate onN-bit data widths, but does so a single bit at a time.
Most of the earlymassive parallel processing machines were built out of individual serial processors, including:
[…] the processor was designed to transfer data serially throughout the entire system. […] The Parallel Multiplier Unit […] by means of a parallel algorithm […](26 pages)
Even operating one bit at a time as a serial computer, the Datapoint 2200 performed considerably faster than the 8008 chip...
[…] TheHP-35 is a totally serial computer. The adder is aBCD serial type […] The serial structure means less integrated circuit area must be allocated to interconnection lines and gating functions and an interesting trade off occurs. A bit-serial, digit-serial architecture is inherently one fourth the speed of a bit-parallel digit-serial structure […] But the basic clock rate for a bit-serial structure can sometimes be increased since additional area can be allocated for larger integrated devices that are necessary for greater speed. In the HP-35, the execution time of the most complex functions is under one second, while the serial architecture permits an increased circuit complexity. […] Instructions in the HP-35 are transferred serially from the active read-only memory to the arithmetic and control circuits and to other ROMs if present. […]