config 'amr tch-* start-mode auto' does not reflect in Channel Activation and Assignment Command
problem in osmo-bsc:
the bts-level configurations
amr tch-f start-mode auto
amr tch-h start-mode auto
are the default settings for each new bts, which should translate to ICMI = 0 in the MultiRate Configuration IE:
.... 0... = ICMI: Initial Codec Mode Indicator: The initial codec mode is defined by the implicit rule provided in 3GPP TS 05.09 (0)
However, the MultiRate Configuration IE always reflects ICMI = 1, meaning
.... 1... = ICMI: Initial Codec Mode Indicator: The initial codec mode is defined by the Start Mode field (1)
problem in ttcn3 tests:
Current ttcn3-bsc-tests expect this erratic behavior, expecting a MultiRate config of '2804'O,
even though no 'amr tch-* start-mode' is set in the config.
The ICMI = 1 is the '8' of '2804'.
The MR config that the ttcn3 tests expect would result from 'start-mode 1', i.e. ICMI = 1 and Start Mode = 0.
(bsc_vty.c subtracts 1 from the argument passed, so that 'start-mode 1' becomes 0 in the MR config bits.)
#1 Updated by neels about 2 months ago
- % Done changed from 0 to 90
patches to fix the tests and osmo-bsc are at https://gerrit.osmocom.org/q/topic:%22amr_startmode%22