Early Computers
The first version of the ENIAC computer was programmed via cabling, switches and plugboards. ENIAC's cabling was later reconfigured to use the existing Function Tables data ROM memory as program ROM memory (the switches and plugboards continued to be used in the reconfigured ENIAC).
Plugboards remained in use in specialty-purpose computers for some time, acting as a ROM but able to be manually reprogrammed in the field. One example is the Ferranti Argus computer, used on the Bristol Bloodhound missile, which feature a plugboard programmed by inserting small ferrite rods into slots, in effect creating a read-only core memory by hand.
Wiring the plugboard "programmed" the system, which operated as a sort of read only memory.
Read more about this topic: Plugboard
Famous quotes containing the word early:
“The girl must early be impressed with the idea that she is to be “a hand, not a mouth”; a worker, and not a drone, in the great hive of human activity. Like the boy, she must be taught to look forward to a life of self-dependence, and early prepare herself for some trade or profession.”
—Elizabeth Cady Stanton (1815–1902)