Step 420–25 minutes
Memory Basics
Random Access Memory (RAM) is where the computer stores the data and instructions it is currently using. Think of it as a massive wall of post-it notes, where each note has a unique address.
Memory Map (RAM)
Address
Value
0x00
9E
0x01
BD
0x02
EC
0x03
5B
0x04
D5
0x05
24
0x06
59
0x07
20
0x08
B1
0x09
A6
0x0A
B2
0x0B
4D
0x0C
1A
0x0D
27
0x0E
AF
0x0F
F0
0x10
60
0x11
99
0x12
CB
0x13
48
0x14
00
0x15
06
0x16
9E
0x17
83
0x18
6F
0x19
04
0x1A
BC
0x1B
FB
0x1C
DF
0x1D
B9
0x1E
61
0x1F
51
0x20
35
0x21
CA
0x22
72
0x23
A4
0x24
F3
0x25
97
0x26
4C
0x27
B8
0x28
0B
0x29
35
0x2A
10
0x2B
81
0x2C
FA
0x2D
FB
0x2E
6E
0x2F
D6
0x30
5E
0x31
A3
0x32
E0
0x33
B3
0x34
3A
0x35
C4
0x36
6A
0x37
90
0x38
AE
0x39
EC
0x3A
02
0x3B
65
0x3C
01
0x3D
F9
0x3E
F9
0x3F
73
Key Concepts
- AddressingEvery byte in RAM has a unique number (address) so the CPU can find it instantly.
- VolatileRAM needs power to keep data. If you turn off the computer, everything in RAM is gone.
Bytes & Words
Computers usually group 8 bits into a Byte. Modern CPUs often work with 64 bits (8 bytes) at a time, which we call a Word.
1
0
0
0
1
1
0
1