PROM

Programmable Read-Only Memory, a memory chip on which data can be written only once. A program that has been written onto a PROM remains there forever. The difference between a PROM and a ROM (read-only memory) is that a PROM is manufactured as blank memory, whereas a ROM is programmed during the manufacturing process. To write data onto a PROM chip, you need a special device called a PROM programmer or PROM burner.

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