Difference between revisions of "PM Opc EX"
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(EX instruction (PLEASE REVIEW!)) |
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=== Execute === | === Execute === | ||
| − | A = Register A | + | A = (8-Bits) Register A |
| − | BA = Register BA: (B shl 8) or A | + | BA = (16-Bits) Register BA: (B shl 8) or A |
; EX BA, A | ; EX BA, A | ||
| Line 23: | Line 21: | ||
; A = Source | ; A = Source | ||
| − | IF (A | + | IF (A AND 0x80) THEN ; Check for sign |
| + | B = 0xFF | ||
| + | ELSE | ||
B = 0x00 | B = 0x00 | ||
| − | |||
| − | |||
ENDIF | ENDIF | ||
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=== Conditions === | === Conditions === | ||
| − | + | None | |
| − | + | === Examples === | |
| − | + | ; A = 0x05 (5) | |
| + | '''EX BA, A''' | ||
| + | ; BA = 0x0005 (5) | ||
| − | == | + | ; A = 0xF9 (-7) |
| + | '''EX BA, A''' | ||
| + | ; BA = 0xFFF9 (-7) | ||
| − | ; A = | + | ; A = 0x00 (0) |
| − | EX BA, A | + | '''EX BA, A''' |
| − | ; BA = | + | ; BA = 0x0000 (0) |
| − | |||
| − | ; A = | + | ; A = 0x7F (127) |
| − | EX BA, A | + | '''EX BA, A''' |
| − | ; BA = | + | ; BA = 0x007F (127) |
| − | |||
| − | ; A = | + | ; A = 0x80 (-128) |
| − | EX BA, A | + | '''EX BA, A''' |
| − | ; BA = | + | ; BA = 0xFF80 (-128) |
| − | |||
[[PM_InstructionList|'''« Back to Instruction set''']] | [[PM_InstructionList|'''« Back to Instruction set''']] | ||
Latest revision as of 00:32, 21 April 2009
EX = Expand Register
| Hex | Mnemonic | Cycles |
|---|---|---|
| CE A8 | EX BA, A | 12 |
Execute
A = (8-Bits) Register A BA = (16-Bits) Register BA: (B shl 8) or A
; EX BA, A ; ; BA = Destination ; A = Source IF (A AND 0x80) THEN ; Check for sign B = 0xFF ELSE B = 0x00 ENDIF
Description
EX expands register A into BA, turning a signed 8-bits value into 16-bits.
Conditions
None
Examples
; A = 0x05 (5) EX BA, A ; BA = 0x0005 (5)
; A = 0xF9 (-7) EX BA, A ; BA = 0xFFF9 (-7)
; A = 0x00 (0) EX BA, A ; BA = 0x0000 (0)
; A = 0x7F (127) EX BA, A ; BA = 0x007F (127)
; A = 0x80 (-128) EX BA, A ; BA = 0xFF80 (-128)
