GE GFK-1541B Network Card User Manual


 
3-30 TCP/IP Ethernet Communications for the Series 90™ PLC User's Manual
May 2002 GFK-1541B
3
(Word 8) Channel Number:
The channel number in Word 8 specifies the channel whose status is
to be read. This value must be a channel number in the range of 1–32 for Series 90-70 PLCs and
1–16 for Series 90-30 PLCs.
(Word 9) Local PLC - Memory Type:
Words 9 and 10 specify the starting point in the client
CPU memory where the Detailed Channel Status words are to be written. The length of the
transfer is implied and is equal to 2 words.
(Word 10) Local PLC - Memory Starting Address:
Word 10 determines the starting address to
store the Detailed Channel Status data. The value entered is the offset (1-based) from the
beginning of PLC memory for the memory type and mode specified in Word 9. This offset will
be either in bits, bytes, or words depending on the mode specified (for example, if Word 9=16 and
Word 10=2, then the starting address will be %I9). Valid ranges of values depend on the PLC’s
memory ranges. The user is responsible for assuring that this area is large enough to contain the 2
words of data without overwriting other application data.
Note
For the Abort Channel and Retrieve Detailed Channel Status commands, no
actual data is transmitted on the network. Communication occurs between the
client PLC CPU and the local Ethernet Interface only. For these commands,
known as “local” commands, the actual function is performed locally within the
Ethernet Interface and then the COMMREQ Status word is sent immediately to
the CPU.