USBB17RX78K4-XXX NEC Electronics, USBB17RX78K4-XXX Datasheet - Page 63

• Manufacturer Part Number: USBB17RX78K4-XXX
• Description: 78K/4 series realtime OS
• Manufacturer: NEC Electronics

4.2.12 prcv_msg (Poll and Receive Message from Mailbox)
54
[Function]
[Remarks]
[System call ID number]
[Parameter]
[Return parameter]
[Assembler format]
[C format]
Receives a message.
If a message has arrived to the mail box indicated by mbxid, it receives the message and sets the top address
of the received message in an address specified by the parameter. In this case, this system call terminates
normally. If the message has not arrived to the mail box, this system call returns “E_PLFAIL” as an error
code. The area for ppk-msg should be allocated by the user.
Received message becomes a top address of the message area actual data is stored.
prcv_msg = 21
mbxid (Mailbox Identifier)
ppk_msg (Pointer of Message Packet)
E_OK
E_PLFAIL
[Large model]
MOV
MOVW
MOV
MOVW
MOV
CALLT
C register = return parameter
ret = prcv_msg (ppk_msg,mbxid);
char
char
bnk0_b, #21
bnk0_d, #mbxid
bnk0_e, #ppk_msg
[40H]
:
**ppk_msg;
*mbxid;
bnk0_up, #mbxid
bnk0_vp, #ppk_msg
CHAPTER 4
Mail box ID (Mailbox top address)
Address of area storing the top
address of received message
Normal termination
Polling failed
[Small model]
MOV
MOVW
MOVW
CALLT
C register = return parameter
RX78K/IV SYSTEM CALL LIST
bnk0_b, #21
[40H]
:
bnk0_up, #mbxid
bnk0_vp, #ppk_msg
- 16 bits (small model)
- 24 bits (large model)
- 16 bits (small model)
- 24 bits (large model)