Programmable Readonly Memory Prom

A PROM is like a ROM except it can be programmed or have information written to it once. This is done before it is installed in the computer. The computer can only read from the PROM and cannot write to it. The PROM contains the specific program instructions for the computer, such as the timing advance curve for a particular engine or the shift points for an automatic transmission. There are other types of programmable ROM being used, such as erasable programmable read only memory (EPROM) which can be erased by ultraviolet light and reprogrammed. Another type is electronically erasable programmable read only memory (EEPROM) which can be erased electronically and reprogrammed. This is all done outside of the computer by the manufacturer.

Do It Yourself Car Diagnosis

Do It Yourself Car Diagnosis

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