Propeller Manual

3: Assembly Language Reference – FRQA, FRQB
FRQA, FRQB
Register: Counter A and Counter B frequency registers.
DAT
〈Label〉 〈Condition〉 Instruction FRQA, SrcOperand 〈Effects〉
DAT
〈Label〉 〈Condition〉 Instruction DestOperand, FRQA 〈Effects〉
DAT
〈Label〉 〈Condition〉 Instruction FRQB, SrcOperand 〈Effects〉
DAT
〈Label〉 〈Condition〉 Instruction DestOperand, FRQB 〈Effects〉
Result: Optionally, the counter frequency register is updated.
•
Label is an optional statement label. See Common Syntax Elements, page 250.
•
Condition is an optional execution condition. See Common Syntax Elements, page 250.
•
Instruction is the desired assembly instruction. FRQA or FRQB may be used in either the
assembly instruction’s DestOperand
or SrcOperand fields.
•
SrcOperand is a constant expression used by Instruction to operate on, and optionally
write to, the
FRQA or FRQB register in DestOperand.
•
DestOperand is a constant expression indicating the register that is operated on, and
optionally written to, using the value of
FRQA or FRQB in SrcOperand.
Explanation
FRQA and FRQB are two of six registers (CTRA, CTRB, FRQA, FRQB, PHSA, and PHSB) that affect the
behavior of a cog’s Counter Modules. Each cog has two identical counter modules (A and B)
that can perform many repetitive tasks. The
FRQA and FRQB registers contain the value that is
accumulated into the
PHSA and PHSB registers, respectively, according to the corresponding
counter’s mode and input stimulus. See the Spin language
CTRA, CTRB section, page 95, for
more information.
FRQA and FRQB are read/write registers and can be used in either the DestOperand or
SrcOperand fields of an assembly instruction. The following code sets
FRQA to $F. See
Registers, page 338, and the Spin language
FRQA, FRQB section, page 111, for more
information.
mov frqa, #$F
Propeller Manual v1.1 · Page 293