Wrong SVC Error code

Register IDN

{ .ulIdn = SIII_SL_IDN(S, 0, 1500, 0, 1), .ulAttribute = VAL_SIII_SL_IDN_ATTR_DISPLAY_FORMAT_BINARY | VAL_SIII_SL_IDN_ATTR_DATA_LENGTH_TWO_BYTE | (1 << SRT_SIII_SL_IDN_ATTR_SCALING), .pszName = "IO Control", .fReadNotify = 1, .fWriteNotify = 1 }

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Now the read to the IDN is delivered to the application. But performing a write there is no notification to the application. The Stack Reports as SVC Error 0xE000 (this is no SVC error code).