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| | Chapter Four |
 | | As with the LOAD instructions, the value stored in either the accumulator or the registers, depending on which instruction is used, is not changed by the execution of the instruction. |
 | | These instructions perform the indicated operations directly on the flags of the processor status register, and their operation, which is self-explanatory, is further described in Appendix 1. |
 | | These four SHIFT instructions are used to multiply or divide by powers of 2, since by rotating bits to the left, we double a number, and by rotating bits to the right, we effectively divide a number by 2. |
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