Description
A read CTE
operation reads a specified number of bytes from the Ethernet configuration
extension table in the specified buffer of
PLC memory. These bytes start with a byte offset at the CTE table
start. The CTE table contents are displayed in the DATABUF output parameter. To program an
MBP_MSTR block to perform a clear remote statistics operation, use function code 11.
Network Implementation
A read CTE operation can be performed on TCP/IP Ethernet and SY/MAX Ethernet networks.
Control Block Usage for TCP/IP Ethernet
Register |
Meaning |
|---|---|
CONTROL[1] |
11 = read CTE |
CONTROL[2] |
Indicates the error status |
CONTROL[3] |
The length setting: a value from 12 to 37 |
CONTROL[4] |
No significance |
CONTROL[5] |
Least significant byte = mapping index Either a value displayed in the byte of the register or is not used. or Most significant byte = network adapter module slot |
CONTROL[6]... CONTROL[9] |
No significance |
Control Block Usage for SY/MAX Ethernet
Register |
Meaning |
|---|---|
CONTROL[1] |
11 = read CTE |
CONTROL[2] |
Indicates the error status |
CONTROL[3] |
Number of words transferred |
CONTROL[4] |
Byte offset in the PLC register structure, specifying from where the CTE bytes are read |
CONTROL[5] |
MSB: slot of the NOE module |
CONTROL[6] ... CONTROL[9] |
Terminator: FF hex |
CTE Indicator Implementation
(DATABUF)
The values in the CTE table are
displayed in the DATABUF output when a CTE read operation
is implemented. The registers display the following CTE data:
CTE indicator implementation (DATABUF):
Parameter |
Register |
Contents |
|---|---|---|
Frame type |
DATABUF[0] |
1 = 802.3 2 = Ethernet |
IP address |
DATABUF[1] |
First byte of the IP address |
DATABUF[2] |
Second byte of the IP address |
|
DATABUF[3] |
Third byte of the IP address |
|
DATABUF[4] |
Fourth byte of the IP address |
|
Lower netmask |
DATABUF[5] |
Most significant word |
DATABUF[6] |
Least significant word |
|
Gateway |
DATABUF[7] |
First byte of the gateway |
DATABUF[8] |
Second byte of the gateway |
|
DATABUF[9] |
Third byte of the gateway |
|
DATABUF[10] |
Fourth byte of the gateway |