Propeller Manual

Assembly Language Reference
are set (1) if the instruction was specified with a WZ and/or WC effect. See Effects on page 291.
The R bit’s default state depends on the type of instruction, but is also affected if the
instruction was specified with the
WR or NR effect. The I field’s default state depends on the
type of instruction and is affected by the inclusion, or lack of, the literal indicator (#) in the
instruction’s source field.
The bits of the CON field usually default to all ones (1111) but are affected if the instruction
was specified with a condition. See
IF_x (Conditions) on page 295.
The last four columns of the opcode table indicate the meaning of the instruction’s output Z
and C flags, the default behavior for writing or not writing the result value, and the number of
clocks the instruction requires for execution.
CLKSET Opcode Table:
–
INSTR– ZCRI
–
CON
–
–
DEST–
–
SRC
–
Z Result C Result Result Clocks
000011 0001 1111 ddddddddd ------000
--- --- Not Written 7..22
Concise Truth Tables
After the opcode table, there is a concise truth table. The concise truth table demonstrates
sample inputs and resulting outputs for the corresponding instruction. Rather than showing
every possible input/output case, the instruction’s concise truth table focuses on exploiting
numerical or logical boundaries that result in flag activity and notable destination output.
This information can aid in learning or verifying the instruction’s intrinsic function and
behavior.
Generally, the concise truth tables should be read carefully from the top row towards the
bottom row. When multiple boundary cases are possible, the related rows are grouped
together for emphasis and separated from other groups by a thick horizontal line.
The following conventions are used:
$FFFF_FFFE; -2 Numbers are values in hexadecimal (left of ‘;’) and decimal (right of ‘;’).
%0_00000011; 3 Numbers are values in binary (left of ‘;’) and decimal (right of ‘;’).
0 –or– 1 Individual zero (0) or one (1) means binary 0 or 1.
wr, wz, wc Assembly effects indicate execution state; write-result, write-z, write-c.
x Lower case “x” indicates items where every possible value applies.
--- Hyphens indicate items that are not applicable or not important.
A good example is the truth table for the
ADDS instruction:
Page 252 · Propeller Manual v1.1