Opcode Table:

–INSTR– ZCR I–CON– –DEST– –SRC–	Z Result	C Result	Result	Clocks
000011 0001 1111 ddddddddd ------110	ID = 0	Prior Lock State	Not Written	8..23

Concise Truth Table:

In					Out
Destination	Source¹	Z	C	Effects	Destination^2, ³	Z	C
$0000_0005; 5	%0_00000110; 6	-	-	wr wz wc	$0000_0005; 5	0	0
$0000_0005; 5	%0_00000110; 6	-	-	wr wz wc	$0000_0005; 5	0	1⁴
$0000_0000; 0	%0_00000110; 6	-	-	wr wz wc	$0000_0000; 0	1	0
$0000_0000; 0	%0_00000110; 6	-	-	wr wz wc	$0000_0000; 0	1	1⁴
$0000_0008; 8 ⁵	%0_00000110; 6	-	-	wr wz wc	$0000_0000; 0	1	1⁴

¹ Source is automatically set to immediate value 6 by the assembler to indicate that this is the LOCKSET hub instruction.
² Destination is not written unless the WR effect is given.
³ Destination Out (written Destination) indicates the ID of the lock bit that was set.
⁴ The C flag indicates the previous state of the lock bit; in these cases the lock bit was already set from the previous example.
⁵ Only the lowest 3 bits of Destination In are utilized, so a value of 8 is seen as lock bit ID 0.

Explanation

LOCKSET is one of four lock instructions (LOCKNEW, LOCKRET, LOCKSET, and LOCKCLR) used to manage resources that are user-defined and deemed mutually exclusive. LOCKSET sets the lock described by the register ID to one (1) and returns the previous state of that lock in the C flag; if the WC effect is specified. The LOCKSET instruction behaves similar to Spin's LOCKSET command; see LOCKSET.

If the WZ effect is specified, the Z flag is set (1) if the ID of the set lock is zero (0). If the WC effect is specified, the C flag is set equal to the previous state of the lock. If the WR effect is specified, the ID of the set lock is written to ID.

LOCKSET is a hub instruction. Hub instructions require 8 to 23 clock cycles to execute depending on the relation between the cog's hub access window and the instruction's moment of execution. See Hub for more information.