Memory Operations

Understanding Memory

Memory is where programs store data that doesn't fit in registers. Our compiler simulates 1024 memory locations, each capable of holding one integer value.

LDR - Load from Memory

LDR loads a value from memory into a register:

LDR Rd, address

Example:

LDR R0, 100      // Load value from memory[100] into R0

STR - Store to Memory

STR stores a register value into memory:

STR Rs, address

Example:

MOV R0, #42
STR R0, 100      // Store R0's value (42) to memory[100]

Complete Example

// Store and load example
MOV R0, #100     // R0 = 100
STR R0, 50       // memory[50] = 100
MOV R0, #0       // Clear R0
LDR R1, 50       // R1 = memory[50] = 100
HALT

Using Memory for Data Storage

// Store multiple values
MOV R0, #10
STR R0, 0        // memory[0] = 10
MOV R0, #20
STR R0, 1        // memory[1] = 20
MOV R0, #30
STR R0, 2        // memory[2] = 30

// Load and sum them
LDR R1, 0        // R1 = 10
LDR R2, 1        // R2 = 20
LDR R3, 2        // R3 = 30
ADD R4, R1, R2   // R4 = 30
ADD R4, R4, R3   // R4 = 60
HALT