It is the read-write memory usable by the operating system and application programs.
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It might be either read-only or read-write memory.
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In some systems, instructions can be stored in read-only memory while data memory generally requires read-write memory.
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Three of the chips were to make a special-purpose CPU with its program stored in ROM and its data stored in shift register read-write memory.
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Almost all microcontrollers have at least two different kinds of memory, a non-volatile memory for storing firmware and a read-write memory for temporary data.
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As expected, the cores were much larger physically than those of read-write core memory.
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Even simple computers usually have one unit to read and write memory, and another to execute user code.
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The CPU is instructed by software to read or write a specific physical memory address.
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For downloading, SanDisk rates the new memory at read and write speeds up to 90MB per second.