Comtrol eCos - Manual (Page 744)

Communication Protocol
This control message involves no further data so the length field should be set to 0. The value field should be
non-zero to enable promiscuous mode, zero to disable it. The request field should be
0x02 . The remaining fields in
the control message will be ignored. It is the responsibility of the host-side device driver to keep track of whether
or not promiscuous mode is currently enabled. It will be disabled when the peripheral changes to Configured state,
typically at the point where the host-side device driver has been activated.
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