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SYNTAX [<LABEL>] XORK <constant>[,<shift>]
OPERANDS 16-bit constant
0 . shift . 15 (defaults to 0)
EXECUTION (PC) + 2 . PC
(ACC(30-0)).XOR.[constant * 2 ^ shift] . ACC(30-0)
(ACC(31)) . ACC(31)
Not affected by SXM.
DESCRIPTION The left-shifted 16-bit immediate constant is exclusive-OR'ed
with the accumulator, leaving the result in the accumulator.
Low-order bits below and high-order bits above the shifted
values are treated as zeros, thus not affecting the
corresponding bits in the accumulator. Note that the most -
significant bit of the accumulator is not affected, regardless
of the shift code value.
WORDS 2
ENCODING 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
+-----------------------------------------------+
|1 1 0 1| shift | 0 0 0 0 0 1 1 0 |
|-----------------------------------------------|
| 16-bit constant |
+-----------------------------------------------+
CYCLES
+------------------------------------------------+
| Cycle Timings for a Single Instruction |
|------------------------------------------------|
| PI/DI | PI/DE | PE/DI | PE/DE | PR/DI | PR/DE |
|-------+-------+-------+--------+-------+-------|
'20 | 2 | 2 | 2+2p | 2+2p | - | - |
|-------+-------+-------+--------+-------+-------|
'C25 | 2 | 2 | 2+2p | 2+2p | 2 | 2 |
|------------------------------------------------|
| Cycle Timings for a Repeat Instruction |
|------------------------------------------------|
'20 | not repeatable | - | - |
|------------------------------------------------|
'C25 | not repeatable |
+------------------------------------------------+
EXAMPLE XORK >FFFF,8
BEFORE AFTER
ACC X >12345678 ACC X >12CBA978
C C