ChibiOS Free Embedded RTOS

Posted: **Wed Dec 05, 2012 5:05 am**

Hi all. I have a problem with MailBox. I don't know what is the different between two functions of MaiBox:

chMBPostAheadS (Mailbox *mbp, msg_t msg, systime_t time)
    //Posts an high priority message into a mailbox.

Code: Select all

chMBPostAheadI (Mailbox *mbp, msg_t msg)
    //Posts an high priority message into a mailbox.

Please help me. Thanks in advance.

Posted: **Wed Dec 05, 2012 6:40 am**

Hi,

Read the "Kernel Concepts" in the kernel manual, the difference is all in the final letter:

I) Is meant to be used from ISRs. within a lock, and does not reschedule internally.
S) Is meant to be used from a thread. within a lock, and reschedules internally.

Note that the "I" version does not wait if the mailbox is full, it is not possible to wait from within an ISR.

Giovanni

ChibiOS Free Embedded RTOS

MailBox: Different between chMBPostAheadS and chMBPostAheadI

MailBox: Different between chMBPostAheadS and chMBPostAheadI

Re: MailBox: Different between chMBPostAheadS and chMBPostAh