OR - Inclusive Logical OR
Usage: OR dest,src
Modifies Flags: CF OF PF SF ZF (AF undefined)
Logical inclusive OR of the two operands returning the result in the destination. Any bit set in either operand will be set in the destination.
| Clocks | ||||
|---|---|---|---|---|
| operands | 286 | 386 | 486 | Size Bytes |
| reg,reg | 2 | 2 | 1 | 2 |
| mem,reg | 7 | 7 | 3 | 2-4 |
| reg,mem | 7 | 6 | 2 | 2-4 |
| reg,immed | 3 | 2 | 1 | 3-4 |
| mem8,immed8 | 7 | 7 | 3 | 3-6 |
| mem16,immed16 | 7 | 7 | 3 | 3-6 |
| accum,immed | 3 | 2 | 1 | 2-3 |
OUT - Output Data to Port
Usage: OUT port,accum
Modifies Flags: None
Transfers byte in AL,word in AX or dword in EAX to the specified hardware port address. If the port number is in the range of 0-255 it can be specified as an immediate. If greater than 255 then the port number must be specified in DX. Since the PC only decodes 10 bits of the port address, values over 1023 can only be decoded by third party vendor equipment and also map to the port range 0-1023.
| Clocks | ||||
|---|---|---|---|---|
| operands | 286 | 386 | 486 | Size Bytes |
| immed8,accum | 3 | 10 | 16 | 2 |
| immed8,accum (PM) | 4/24 | 11/31/29 | 2 | |
| DX,accum | 3 | 11 | 16 | 1 |
| DX,accum (PM) | 5/25 | 10/30/29 | 1 | |
| 386+ protected mode timings depend on privilege
levels.
first number is the timing when: CPL <= IOPL |
||||
OUTS - Output String to Port (80188+)
Usage: OUTS port,src
OUTSB
OUTSW
OUTSD (386+)
Modifies Flags: None
Transfers a byte, word or doubleword from "src" to the hardware port specified in DX. For instructions with no operands the "src" is located at DS:SI and SI is incremented or decremented by the size of the operand or the size dictated by the instruction format. When the Direction Flag is set SI is decremented, when clear, SI is incremented. If the port number is in the range of 0-255 it can be specified as an immediate. If greater than 255 then the port number must be specified in DX. Since the PC only decodes 10 bits of the port address, values over 1023 can only be decoded by third party vendor equipment and also map to the port range 0-1023.
| Clocks | ||||
|---|---|---|---|---|
| operands | 286 | 386 | 486 | Size Bytes |
| port,src | 5 | 14 | 17 | 1 |
| port,src (PM) | 8/28 | 10/32/30 | 1 | |
| 386+ protected mode timings depend on privilege
levels.
first number is the timing when: CPL <= IOPL |
||||
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