Shift left

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Syntax

Syntax: shift_left register1, register2

  • register1 = Register to shift left
  • register2 = Shift left by value of register2

Use

Used to execute a logical bitwise operation shift left. Use shift_right to shift right.
In the example below we'll use R1 to store a 7Bit value 100 decimal (127 decimal value maximum) and 2 seperate flags set true.

1100100 = 100 Decimal
1 = Flag 1 true
1 = Flag 2 true
Value to store 00000000000000000000000110010011 (403 decimal, 193 hex)

Example


100:     leti R1, 00000193 //Set R1 to 403 (00000000000000000000000110010011 in binary)
         let R2, R1 //This will be used for 7bit value
         leti R5, 00000002 //This will be used to store the SHIFT amount
         andi R2, 000001FC //Perform bitwise AND operation on R2 using 00000000000000000000000111111100 binary. R2 now equals 00000000000000000000000110010000
         shift_right R2, R5 //Perform bitwise SHIFT RIGHT on R2. Value changed from 400 (00000000000000000000000110010000) to 100 (00000000000000000000000001100100)
         let R3, R1 //This will be used to store the first flag
         andi R3, 00000001 //Perform bitwise AND operation on R2 using 00000000000000000000000000000001 binary. R2 now equals 1
         let R4, R1 //This will be used to store the second flag
         leti R5, 00000001 //This will be used to store the SHIFT amount
         andi R4, 00000002 //Perform bitwise AND operation on R4 using 00000000000000000000000000000010 binary. R2 now equals 2
         shift_right R4, R5 //Perform bitwise SHIFT RIGHT on R4. Value changed from 2 (00000000000000000000000000000010) to 1 (00000000000000000000000000000001)
         ret 

Also see

List of OP Codes used in example.