Dialogue

Anton: What is the purpose of using computers on board the car?

Vlad: As I know computer is used to advance the engine operation as well as the performance of other units.

A.: What components does the on-board computer consist of?

V.: It consists of two components. One is the hardware and the other is the software.

A.: What is hardware?

V.: The computer hardware uses a Central Processing Unit (CPU) which is referred to as a microprocessor.

A.: What is software?

V.: The computer software on a car carries a program. The pro­gram tells the computer what to do and when to do it.

A.: And where is the program stored?

V.: It is stored in a permanent memory which is called Read Only Memory (ROM).

A.: And what is Programmable Read Only Memory (PROM)? What is the difference between ROM and PROM?

V.: In case the memory becomes defective PROM can be readily removed and replaced, while ROM cannot.

A.: And what is RAM?

V.: RAM is Random Access Memory (main memory), which can be accessed without going through a specific sequence. The technician interfaces with RAM whenever trouble codes are accessed.

A.: Thanks a lot for your explanation.

V.: You are welcome. See you later.