OPTO 22 SNAP-PAC-S1, Руководство пользователя

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CHAPTER 3: MAINTENANCE AND TROUBLESHOOTING
SNAP PAC S-Series User’s Guide 43
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Within the
sdcard0
directory, you can create other directories and files as needed, up to a
maximum of 512 in the sdcard0 directory. 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.
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
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/
When the microSD card is in the controller, the STAT LED blinks briefly about once every five seconds,
indicating that the controller has scanned it and knows it is there.
NOTE: If you access the card when it is not in the controller (for example, if it is in a card reader), the sdcard0
directory does not appear. Do NOT create it. It automatically appears when the card is in the controller.
Displaying Free Space on the Card
(Requires firmware 8.5a or newer.) 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. In a PAC Control strategy, for example, you could notify an operator if the card needs
replacing, based on the number of bytes still unused.
1. Make sure the card is in the controller.
2.
In PAC Control, use the command Read Number from I/O Unit Memory Map to read memory
map address FFFFF7002204. Use Integer 32 Variable in Argument 2.
For more information, see “I/O Unit—Memory Map Commands” in Chapter 10 of the PAC
Control User’s Guide, and see “Read Number from I/O Unit Memory Map” in the Command
Reference or Help.)
3.
In PAC Manager, open the Inspect window for the controller. Click Other and choose Generic
Read/Write from the popup menu. In the Address field, type F7002204. From the Type
dropdown list, choose 32-bit Integer. Leave the Length as 1. Click Refresh.
The number of bytes appears in the Value column.
Updating Firmware
The card can also be used to update firmware if the controller is not on the network, or if PAC
Manager isn’t available.
NOTE: The controller must have firmware version R8.4a or higher and loader version 5.1b or higher to use
the microSD card in this way.