T-Kernel Specification (1.B0.02)

4.7. TIME MANAGEMENT FUNCTIONS 169
tk cre cyc
Create Cyclic Handler
[C Language Interface]
ID cycid = tk_cre_cyc ( T_CCYC *pk_ccyc ) ;
[Parameters]
T CCYC* pk ccyc Address of cyclic handler definition packet
pk ccyc detail:
VP exinf Extended information
ATR cycatr Cyclic handler attributes
FP cychdr Cyclic handler address
RELTIM cyctim Cycle time
RELTIM cycphs Cycle phase
(Other implementation-dependent parameters may be added beyond this point.)
[Return Parameters]
ID cycid Cyclic handler ID
or Error Code
[Error Codes]
E OK
E NOMEM
E LIMIT
E RSATR
E PAR
Normal completion
Insufficient memory (memory for control block cannot be allocated)
Number of cyclic handlers exceeds the system limit
Reserved attribute (cycatr is invalid or cannot be used)
Parameter error (pk ccyc, cychdr, cyctim, or cycphs is invalid or cannot be used)
[Description]
Creates a cyclic handler, assigning to it a cyclic handler ID. A cyclic handler is a handler running at
designated intervals as a task-independent portion.
exinf can be used freely by the user to set miscellaneous information about the created cyclic handler.
The information set in this parameter can be referenced by tk ref cyc. If a larger area is needed for
indicating user information, or if the information may need to be changed after the cyclic handler is
created, this can be done by allocating separate memory for this purpose and putting the memory packet
address in exinf. The OS pays no attention to the contents of exinf.
cycatr indicates system attributes in its low bits and implementation-dependent information in the
high bits. Designation in the system attributes part of cycatr is as follows.
Copyright c○ 2002, 2003 by T-Engine Forum
T-Kernel 1.B0.02