This is an old revision of the document!
Table of Contents
MPINO STUDIO 2 Phase 4-6 · Bitwise Operation Box Functions
These commands apply logic, shift, or rotate operations to the bits in a WORD.
This ladder screen compares the input forms of WAND, SHL, and ROL.
1. Common Rules
Bit-operation commands process all 16 bits in a WORD. A shift discards bits that leave the word and fills with zero; a rotate brings those bits back at the opposite end.
2. WAND, WOR, and WXOR
WAND
Word AND
Applies bitwise AND to two WORD values and stores the result.
Syntax: WAND D0 D1 D2
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x00CC, D1=0x00AA | WAND D0 D1 D2 | D2=0x0088 |
WOR
Word OR
Applies bitwise OR to two WORD values and stores the result.
Syntax: WOR D0 D1 D2
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x00CC, D1=0x00AA | WOR D0 D1 D2 | D2=0x00EE |
WXOR
Word XOR
Applies bitwise XOR to two WORD values and stores the result.
Syntax: WXOR D0 D1 D2
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x00CC, D1=0x00AA | WXOR D0 D1 D2 | D2=0x0066 |
3. WNOT
Word NOT
Inverts every bit in the source WORD and stores the result.
Syntax: WNOT D0 D1
Arguments
- 1st = S: source address or constant to invert
- 2nd = D: result destination address
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x00CC | WNOT D0 D1 | D1=0xFF33 |
4. SHL and SHR
SHL
Shift Left
Shifts a WORD left and stores the result. Bits leaving the left are discarded and zeros fill from the right. Use a shift count from 0 to 15.
Syntax: SHL D0 2 D1
Arguments
- 1st = source: integer WORD address
- 2nd = shift count: 0 to 15
- 3rd = destination: result address
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x0003 | SHL D0 2 D1 | D1=0x000C |
SHR
Shift Right
Logically shifts a D WORD right and stores the result. Bits leaving the right are discarded and zeros fill from the left.
Syntax: SHR D0 1 D1
Arguments
- 1st = source: D WORD address
- 2nd = shift count: 0 to 15
- 3rd = destination: result address
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x000C | SHR D0 1 D1 | D1=0x0006 |
5. ROL and ROR
ROL
Rotate Left
Rotates a D, C, or T WORD left. Bits leaving the left return at the right end.
Syntax: ROL D0 2 D1
Arguments
- 1st = source: D, C, or T WORD address
- 2nd = rotate count
- 3rd = destination: D, C, or T WORD address
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x8001 | ROL D0 2 D1 | D1=0x0006 |
ROR
Rotate Right
Rotates a D, C, or T WORD right. Bits leaving the right return at the left end.
Syntax: ROR D0 1 D1
Arguments
- 1st = source: D, C, or T WORD address
- 2nd = rotate count
- 3rd = destination: D, C, or T WORD address
| Run condition | Before | Command entered | Expected result |
|---|---|---|---|
| Left condition ON | D0=0x0003 | ROR D0 1 D1 | D1=0x8001 |
6. Troubleshooting
| Symptom | What to check |
|---|---|
| A sign bit does not fill the left side during a right shift. | SHR is a logical shift that fills the upper empty bits with zero. |
| Bits disappear after a shift. | Use ROL or ROR instead of SHL or SHR when the shifted-out bits must be preserved. |