Memories And Files Of Q12Dccpu-V; Memory Type - Mitsubishi Electric MELSEC Q Series User Manual

18.4

Memories and files of Q12DCCPU-V

The following describes the available memories and files that can be stored in Q12DCCPU-V.
18.4.1

Memory type

The following memories are available.
• System ROM ............................................ Page 329, (1) in this section
• Standard ROM .......................................... Page 329, (2) in this section
• Work RAM/RAM disk ................................ Page 329, (3) in this section
• Battery backup RAM/Standard RAM ........ Page 330, (4) in this section
• CompactFlash card................................... Page 331, (5) in this section
• CPU shared memory ................................ Page 331, (6) in this section
(1) System ROM
A system ROM is a memory that stores system software and VxWorks image files required for operations of the C
Controller module.
(2) Standard ROM
A standard ROM is a memory that store files such as user programs.
Since a standard ROM is a flash ROM, write count (life) is limited.
For the procedures to check the life and writing frequency of a standard ROM, refer to the following.
Page 137, Section 9.4
(3) 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
CHAPTER 18 MEMORIES AND FILES
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