User Manual

Appendix • 183
Mailbox Command References
WAGO-I/O-SYSTEM 750
I/O Modules
6.3.6.6 Read Available Hopping Channels (GetAvailableChannelMap, 0xD8)
Call up returns information on the status of the environment (i.e., the status of
the wireless medium) for a connection channel. For Bluetooth
®
, the channels
available for hopping are indicated. There are 79 channels with 1 MHz avail-
able. The channels are numbered serially from 0 through 78. The frequency of
each channel is based on the channel number:
Frequency of the channel = 2402 + channel number MHz
The WAGO Bluetooth
®
module supports AFH (adaptive frequency hopping).
If individual frequency ranges are recognized as defective (for example, if
other wireless technologies with higher signal strength in this range are send-
ing), the corresponding channels of its own transmission are excluded. This
reduces interference and improves the connection quality for the Bluetooth
®
network, as well as for the third-party system. A positive side effect is the pos-
sibility of making connections through third-party activity in the 2.4 GHz ISM
band using the list of the channels masked in this manner. The rule of thumb
is: The greater the number of channels available for hopping, the better the
status of the wireless medium.
Conditions
Mailbox size Operating mode/profile Device role
6 12 18 Config.
Real-
time
Ad hoc Master Slave
Save
config.
Restart
- ● ● - ● ● ● ● - -
Request
Byte 2
7
2
6
2
5
2
4
2
3
2
2
2
1
2
0
0 MBX_GETAVAILABLECHANNELMAP
1 T -
2 MBX_TARGET_TABLE_AND_INDEX
Arguments
Parameter Value Description
Bit 0…3 Table Index
Index 0...6 for WAGO devices of slots 1...7
Index 0...5 for external devices of slots 8...12
MBX_TARGET_TABLE_
AND_INDEX
Bit 4…7 Target table
"2" for WAGO_DEVICE (slots 1...7)
"1" for EXTERNAL_DEVICE (slots 8...12)