T-Kernel Specification (1.B0.02)

46 CHAPTER 4. T-KERNEL/OS FUNCTIONS
tk set reg
Set Task Registers
[C Language Interface]
ER ercd = tk_set_reg ( ID tskid, T_REGS *pk_regs, T_EIT *pk_eit, T_CREGS *pk_cregs ) ;
[Parameters]
ID tskid Task ID
T REGS pk regs General registers
T EIT pk eit Registers saved when EIT occurs
T CREGS pk cregs Control registers
The contents of T REGS, T EIT, and T CREGS are defined for each CPU and implementation.
[Return Parameters]
ER ercd Error code
[Error Codes]
E OK
E ID
E NOEXS
E OBJ
E CTX
E PAR
Normal completion
Invalid ID number (tskid is invalid or cannot be used)
Object does not exist (the task designated in tskid does not exist)
Invalid object state (called for the invoking task)
Context error (called from task-independent portion)
Invalid register value (implementation-dependent)
[Description]
Sets the current register contents of the task designated in tskid.
If NULL is set in pk regs, pk eit, or pk cregs, the corresponding registers are not referenced.
The set register values are not necessarily the values while the task portion is executing. The OS is not
aware of the effects of register value changes. It is possible, however, that some registers or register bits
cannot be changed if the OS does not allow such changes (implementation-dependent).
If this system call is issued for the invoking task, error code E OBJ is returned.
Copyright c○ 2002, 2003 by T-Engine Forum
T-Kernel 1.B0.02