OPTO 22 SNAP-PAC-R1, Руководство пользователя

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CHAPTER 4: MAINTENANCE AND TROUBLESHOOTING
SNAP PAC R-Series Controller User’s Guide
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Within the
sdcard0
directory on the controller (or the root if the card is in a card reader),
you can create other directories and create or add files, up to a maximum of 512 files and
directories. In subdirectories of sdcard0, however, you can include many more files. The total
number of files and directories on the micoSD card cannot exceed 65,500.
Remember that all files must be named with a maximum of eight characters in the name
plus three characters in the extension (8 dot 3 format), for example:
datafile.txt
When the card is in the controller, you can access files on the card through PAC Control
commands and from a PC using FTP.
Use PAC Control commands just as you would with any other file in the controller’s file
system. See the section “Using the Control Engine’s File System” in Chapter 10 of the PAC
Control User’s Guide (form #1700) for help. Remember to include the card’s directory name in
the path in the file communication handle, for example:
file:a,/sdcard0/VoltLog.txt
Note that the path separator is a forward slash (/), not a backward slash (\).
You can also use the FTP communication handle in PAC Control to manipulate files. See the
section “Moving Files via FTP,” also in Chapter 10 of the
PAC Control User’s Guide .
To move files to or from a PC , use any standard FTP software. (Don’t use PAC Manager as
the FTP client, as it cannot see directories within the controller’s file system). Remember to
include the card’s directory name, for example:
ftp://192.168.1.1/sdcard0/
NOTE: If you access the card when it is not in the controller (for example, in a card reader), the
sdcard0 directory does not appear. Do NOT create it. The controller treats the card as a folder in
the controller’s file system.
Displaying Free Space on the Card
If you need to know how many free bytes are left on a microSD card, you can use PAC
Control or PAC Manager to read this data from an address in the controller’s memory map.
microSD card
Files in PAC’s file system