LDM

Name

Branch Back and Load

Function

The 4 bits of immediate data encoded in the instruction are loaded
into the accumuator, then execution continues with the most recent address
on the stack. contents of the accumulator. The carry bit is not affected.

Syntax

LDM(D)

Assembled

Binary

1100 DDDD

Decimal

208, then incrementing by 1 until 223 (1st word).

Hexadecimal

0xD0, then incrementing by 1 until 0xDF (1st word).

Symbolic

 ../../_images/ldm-sym.png

Execution

1 word, 8-bit code and an execution time of 10.3 \({\mu}\) sec

Side-effects

Not Applicable

Implemented

ldm

Detailed Description

The 4 bits of immediate data are loaded into the accumulator.

The carry bit is not affected.

../../_images/ldm.png

Example Program

/ Example program
        ldm   0
        ldm   9
        ldm   15
        end

The above program will first clear the accumulator (setting all 4 bits to 0), then load the value 9 into the accumulator, then finally, set all the accumulator’s 4 bits by loading the value 15.