9 Further Notes on Operation
Behavior after Memory Reset
The CPU in the S7 station does not recognize that the CP memory was reset. The CP therefore changes to the “stopped with error” state (see Chapter 4).
The configuration data must then be reloaded.
You can initiate this loading by turning the power off and on again.
9.2Working with Fast Ethernet − automatic switchover
How Automatic Switchover of the Network Settings Works
The CP has two 10/100 Mbps half/full duplex ports with autosensing and autonegotiation of the network settings. After turning on the CP, these functions work as explained below:
SThe CP attempts to detect the transmission rate (10/100 Mbps) being used by the partner.
If no connection is established between partners in PROFINET IO mode, you should check whether the devices involved are set to “automatic setting” or 100 Mbps full duplex.
SIf detection is possible, the CP attempts to negotiate a full duplex with the partner.
SIf no negotiation is possible, the CP uses the previously detected transmission rate and half duplex.
Duration of the procedure: up to 2 seconds
You set the network properties of the CP in STEP 7 in the properties dialog of the CP, “Port Parameters” tab.
Autocrossing
The automatic setting also includes an “autocrossing” mechanism. With autocrossing, you can connect network components and end devices using either crossover or straight−through cables.
CP | B3L−47 |
Release 03/2007 |
