Mitsubishi Electric Q80BD-J71GP21-SX User Manual page 175

12
APPLICATION FUNCTIONS
< Precautions for using RECV function >
When receiving data to the multiple channels of the board, create a user program
1
to read data from all channels that receive data.
If a channel from which data are not read exists in the channel from which data are
received, the received data of the channel from which data are not read are
accumulated in the reception buffer of the driver and all area of 128 data are
occupied.
In this case, the received data of other channels cannot be read because the driver
automatically discards subsequent data received by the board.
When attempting data read by executing the mdReceive/mdReceiveEx function
2
immediately after the send data completion at the sending station, an error, "71
(0047 ): No reception data error", occurs because the driver has not completed
H
the RECV function and thus the receive data have not yet stored to the reception
buffer of the driver.
Retry the operation after waiting for a while.
When attempting data send consecutively, an error, "Channel busy (dedicated
3
instruction) error", occurs at the sending station because the channel is being used
by the driver and thus the sent data cannot be received.
Follow the measures described below.
(a) Retry the operation after waiting for a while.
(b) Change the target station channel.
12.1 Transient Transmission Function
12.1.4 SEND/RECV function
9
10
11
12
13
14
A
I
12
- 19