prcv_mbx

Outline

Receive from mailbox (polling).

C format

 ER      prcv_mbx ( ID mbxid, T_MSG **ppk_msg );


Assembly format

 MOVW    BC, #LOWW(_ppk_msg)
 MOV     A, #mbxid
 CALL    !!_prcv_mbx


Parameter(s)

I/O

Parameter

Description

I

 ID      mbxid;
ID number of the mailbox from which a message is received.

O

 T_MSG   **ppk_msg;
Start address of the message packet received from the mailbox.



Explanation

This service call receives a message from the mailbox specified by parameter mbxid, and stores its start address in the area specified by parameter ppk_msg.

If the message could not be received from the target mailbox (no messages were queued in the wait queue) when this service call is issued, message reception processing is not executed but "E_TMOUT" is returned.

Note For details about the message packet, refer to "12.5.5 Message packet".

Return value

Macro

Value

Description

E_OK

0

Normal completion.

E_TMOUT

-50

Polling failure.