Download 80296SA Microcontroller User`s Manual

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80296SA USER’S MANUAL
Table A-6. Instruction Set (Continued)
Mnemonic
EXTB
Operation
Instruction Format
SIGN-EXTEND SHORT-INTEGER INTO
INTEGER. Sign-extends the low-order byte
of the operand throughout the high-order byte
of the operand.
EXTB
wreg
(00010110) (wreg)
if
DEST.7 = 1 then
(high byte DEST) ← 0FFH
else
(high byte DEST) ← 0
end_if
PSW Flag Settings
IDLPD
Z
N
C
V
VT
ST
✓
✓
0
0
—
—
IDLE/POWERDOWN/STANDBY. Depending
on the 8-bit value of the KEY operand, this
instruction causes the device to:
•
•
•
•
enter idle mode, if KEY=1,
enter powerdown mode, if KEY=2,
enter standby mode, if KEY=3,
execute a reset sequence,
if KEY = any value other than 1, 2, or 3.
The bus controller completes any prefetch
cycle in progress before the CPU stops or
resets.
if KEY = 1 then
enter idle
else if KEY = 2 then
enter powerdown
else if KEY = 3 then
enter standby
else
execute reset
PSW Flag Settings
Z
N
C
V
VT
ST
KEY = 1, 2, or 3
—
—
—
—
—
—
KEY = any value other than
1, 2, or 3
0
A-20
0
0
0
0
0
IDLPD
#key
(11110110) (key)