Imagine a computer system that contains physical main memory of 1 Gigabyte and a 64bit address space. You can assume that a memory cell is one byte(8bits) long.
1. How many bits are needed to address the physical main memory?
2. How many memory cells can be addressed with the given 64bit address
space? how many petabyte(2^50) can be addressed?
1. A GB is 2^30 bytes. Addressing is a matter of powers of 2. A 0 bit address could only address 1 location (2^0 = 1); 1 bit allows 2 locations (2^1 = 2), etc.
2. See above; 64 bits - 50 bits = 14 bits, so that gives you 2^14 chunks of 2^50 bytes (or 2^64 / 2^50 = 2^14)
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