Propeller Manual

3: Assembly Language Reference – SHL
SHL
Instruction: Shift value left by specified number of bits.
SHL Value, 〈#〉 Bits
Result: Value is shifted left by Bits.
•
Value (d-field) is the register to shift left.
•
Bits (s-field) is a register or a 5-bit literal whose value is the number of bits to shift
left.
Opcode Table:
–INSTR– ZCRI –CON– –DEST– –SRC– Z Result C Result Result Clocks
001011 001i 1111 ddddddddd sssssssss
Result = 0 D[31] Written 4
Concise Truth Table:
In Out
Destination Source Z C Effects Destination Z C
$8765_4321; -2,023,406,815 $0000_0004; 4 - -
wz wc
$7654_3210; 1,985,229,328 0 1
$7654_3210; 1,985,229,328 $0000_000C; 12 - -
wz wc
$4321_0000; 1,126,236,160 0 0
$4321_0000; 1,126,236,160 $0000_0010; 16 - -
wz wc
$0000_0000; 0 1 0
Explanation
SHL (Shift Left) shifts Value left by Bits places and sets the new LSBs to 0.
If the
WZ effect is specified, the Z flag is set (1) if the resulting Value equals zero. If the WC
effect is specified, the C flag is set equal to Value’s original bit 31. The result is written to
Value unless the
NR effect is specified.
Propeller Manual v1.1 · Page 347