Mitsubishi Electric MELSEC iQ-R Series User Manual page 51

■User program execution
Execute a user program by starting a task from the script file. The system may malfunction if the user program is executed
without the task being started.
■Startup of a task performing floating-point operations
Always specify the VX_FP_TASK option for the third argument of taskSpawn when activating the following tasks.
• A task performing floating-point operations
• A task calling a function that returns floating-point value
• A task calling a function that takes floating-point value as an argument
• A task calling a data analysis function
• A task calling a statistical analysis function
Activating the above task without the VX_FP_TASK option specified may cause the operating system runaway. For
information on specifying the VX_FP_TASK option in a script file, refer to the following section.
Page 52 Creating Script File
For more details on the VX_FP_TASK option, refer to the manual for VxWorks.
■Task execution in STOP or PAUSE status
Even if the operating status of the C Controller module is STOP or PAUSE, the user program task does not stop. Use the C
Controller module dedicated function (CCPU_GetCpuStatus) to split the user program processing according to the operating
status of the Controller module.
■Priority of tasks to be executed
Set the priority of a task to execute a user program as described below.
• When access is not made with FTP during user program execution, set the priority of the user program to 100 or more (100
to 255). Operating with the priority set to 0 to 99 may cause improper operation of the system.
• When the access is made with FTP while executing a user program, the actual FTP processing (task) of the C Controller
module is performed at the priority of 200. Set the priority of the user program to 201 to 255. When setting the priority to 100
to 200, set a wait processing (such as taskDelay) in the user program to let the actual FTP processing operate.
■Communication with a target device via Ethernet
To communicate with a target device via Ethernet, check the port number being used in the C Controller module in advance
using the VxWorks standard "netstat" command
communication may not be performed if used.
*1 Execute the "netstat" command using the Telnet tool.
■When no response is returned from a function
The response from a function may not be returned when an error occurs on a C Controller module. Design a user program
take into account the possibility of no response from the function. The error occurrence status can be checked using the C
Controller module dedicated function (CCPU_GetErrInfo).
■Memory fragmentation
Allocating and deallocating memory frequently may cause improper operation of the system due to memory fragmentation.
■Restrictions on MELSEC data link functions
A path for a MELSEC data link function does not support to be shared among multiple tasks. Make sure to manage a path
opening/closing for each task.
■When changing system clock rate
• Use the C Controller module dedicated function (CCPU_SysClkRateSet) to change the system clock rate, and do not use
the VxWorks standard API function (sysClkRateSet). Otherwise, the operation of VxWorks will be unstable.
*1
. Do not use any port number that has already been used. Normal
6 PROCEDURE BEFORE OPERATION
6.10 Creating User Program
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