User Manual
iM871A Wireless M-Bus
Module Firmware
iM871A_WMBus_UserManual.docx, Wireless Solutions, v1.2
Page 11
WM-Bus Mode R2
Frequent receive mode
Mode R2 bidirectional, meter always available
Transmission at channel 0-9, chip rate: 4.8 kcps, encoding: "Manchester"
Receiving at 868.33 MHz (channel 5), chiprate 4.8 kcps, decoding: "Manchester"
Once a mode is configured the module firmware configures all required physical parameter
automatically according to EM 13757-4.
Telegram Format A
WM-Bus Mode C
Compact mode
Mode C1 unidirectional, compact operation
Mode C2 bidirectional, compact operation
Transmission at 868.95 MHz, chip rate: 100 kcps, encoding: "NRZ"
Receiving (meter) at 869,525 MHz, chip rate: 50 kcps, decoding: "NRZ"
Telegram Format A / Telegram Format B
Note: The iM871A can be used as RF-Adapter for Wireless M-Bus devices. It
provides the physical access to the Wireless M-Bus "Network". For complete
Wireless M-Bus protocol operation a host controller is needed which is able to
generate telegrams which meet the EN13757-3 requirements.
Some M-Bus modes require response times which cannot be fulfilled with an
external host controller due to long transmission times on the wired interface. For
these cases we can provide customized solutions.
