Propeller Manual

RCR – Assembly Language Reference
RCR
Instruction: Rotate C right into value by specified number of bits.
RCR Value, 〈#〉 Bits
Result: Value has Bits copies of C rotated right into it.
•
Value (d-field) is the register in which to rotate C rightwards.
•
Bits (s-field) is a register or a 5-bit literal whose value is the number of bits of Value
to rotate C rightwards into.
Opcode Table:
–INSTR– ZCRI –CON– –DEST– –SRC– Z Result C Result Result Clocks
001100 001i 1111 ddddddddd sssssssss
Result = 0 D[0] Written 4
Concise Truth Table:
In Out
Destination Source Z C Effects Destination Z C
$0000_0001; 1 $0000_0000; 0 - x
wz wc
$0000_0001; 1 0 1
$0000_0001; 1 $0000_0001; 1 - 0
wz wc
$0000_0000; 0 1 1
$0000_0001; 1 $0000_0001; 1 - 1
wz wc
$8000_0000; -2,147,483,648 0 1
$18C2_1084; 415,371,396 $0000_0002; 2 - 0
wz wc
$0630_8421; 103,842,849 0 0
$18C2_1084; 415,371,396 $0000_0002; 2 - 1
wz wc
$C630_8421; -969,898,975 0 0
$8765_4321; -2,023,406,815 $0000_0004; 4 - 0
wz wc
$0876_5432; 141,972,530 0 1
$8765_4321; -2,023,406,815 $0000_0004; 4 - 1
wz wc
$F876_5432; -126,462,926 0 1
Explanation
RCR (Rotate Carry Right) performs a rotate right of Value, Bits times, using the C flag’s
original value for each of the MSBs affected.
If the
WZ effect is specified, the Z flag is set (1) if the resulting Value equals zero. If the WC
effect is specified, at the end of the operation, the C flag is set equal to Value’s original bit 0.
The result is written to Value unless the
NR effect is specified.
Page 334 · Propeller Manual v1.1