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Shift Register
This InstructionSFT(010) is controlled by three execution conditions, I, P and R.If SFT(010) is executed and (a) execution condition P is ON and was OFF the last execution and (b) R is OFF, then execution condition I is shifted into the rightmost bit of a shift register defined between St and E, that is, if I is ON, a 1 is shifted into the register; if I is OFF, a 0 is shifted in. When I is shifted into the register, all bits previously in the register are shifted to the left and the leftmost bit of the register is lost.The execution condition on P functions like a differentiated instruction, that is, I will be shifted into the register only when P is ON and was OFF the last time SFT(010) was executed. If execution condition P has not changed or has gone from ON to OFF, the shift register will remain unaffected.St designates the rightmost word of the shift register; E designates the leftmost. The shift register includes both of these words and all words between them. The same word may be designated for St and E to create a 16-bit (that is, 1-word) shift register.When execution condition R goes ON, all bits in the shift register will be turned OFF (that is, set to 0) and the shift register will not operate until R goes OFF again.
Example for use SFT
From this sample data will shift every 1 second by shift from word
15 to word 17 we can ladder like this
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