Mitsubishi Electric MELSEC Q Series User Manual page 321

(4) Work RAM / RAM disk
(a) Work RAM
A work RAM is a volatile memory for program execution.
The following programs and software are read and executed in a work RAM.
• User programs stored into a standard ROM, and SD memory card
• C Controller module's OS and system software stored in the system ROM
A work RAM cannot store files. To store files, create a RAM disc within a work RAM.
(b) RAM disk
Create the VxWorks function in a work RAM by the user program.
It can be accessed from FTP, Telnet and user programs and store files.
● Since this is a volatile memory, files are lost upon power OFF. Use it when creating temporary files.
● A sample program to create a RAM disc (MakeRAMDisk) is stored in Setting/monitoring tools for the C Controller
module.
Setting/Monitoring Tools for the C Controller Module Version 4 Operating Manual
(5) Battery backup RAM / Standard RAM
(a) Battery backup RAM
A battery backup RAM is a memory that stores data that need to be retained through power OFF among data
used by user programs, etc.
Access to a battery backup RAM from the C Controller module dedicated function by using the user program is
allowed. Functions used are indicated below.
Function name
CCPU_WriteSRAM
CCPU_ReadSRAM
CCPU_WriteSRAM_ISR
CCPU_ReadSRAM_ISR
Remark
For C Controller module dedicated function, refer to the following.
Page 353, CHAPTER 20
A battery backup RAM cannot store files. To store files, create a standard RAM area within a battery backup
RAM.
Writes data to the battery backup RAM.
Reads data from the battery backup RAM.
Writes data to the battery backup RAM.
Executable from the interrupt service routine.
Reads data from the battery backup RAM.
Executable from the interrupt service routine.
CHAPTER 18 MEMORIES AND FILES
Function
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