RCX_SET_HANDSHAKE_CONFIG_REQ does not change the handshake mode

Using RCX_SET_HANDSHAKE_CONFIG_REQ to change the handshake mode of the input process data bPDInHskMode = 0x02 (RCX_IO_MODE_BUFF_DEV_CTRL).
The request is either returned with error state 0xC0000120 (TLR_E_CONFIGURATION_FAULT), if the stack is already configured (BUS is not started).

Or if the stack is not configured (request is sended before downloading and starting a configuration database), the command is answered without an error state, but the information in NETX_COMMON_STATUS_BLOCK.bPDInHskMode still shows the state 0x04 = RCX_IO_MODE_BUFF_HST_CTRL, like configured in the database.