Asked by: Sohaila Bertholdt
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What does LDR do in lc3?

Last Updated: 2nd April, 2020

LDR stores the source register's value plus an immediate value offset and stores it in the destination register. LDI treats the source register as an address and stores the contents of memory at that address in the destination register. This function stores a value (source label) into a destination register.

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Similarly, it is asked, what does STR do in lc3?

This function stores a value (source label) into a destination register. STR stores the value in a source register into a destination register. An immediate offset may also be used.

Additionally, how many bits are used to identify the program counter offset in an lc3 instruction? The LC-3 ISA has 15 instructions, each identified by its unique opcode. The opcode is specified by bits [15:12] of the instruction. Since four bits are used to specify the opcode, 16 distinct opcodes are possible. However, the LC-3 ISA specifies only 15 opcodes.

In this way, what does .fill do in lc3?

fill: tells assembler, put these bits into a word. . string: convert text to . FILL w/ one ascii code per word, NUL terminated.

What is the operation of the ST instruction?

Operation[edit] The ST instruction takes the 32-bit integer value contained in the source register specified by the first argument and stores that value in the memory address specified by the second argument (the target address).

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