Hi,
Yes, FCM service can be used to receive data on COM1.For this purpose, adl_FcmSubscribe() should be used to subscribe the FCM service on a specific port(say COM1 in your case),to open the requested port and to set the control and data handler. On successful subscription,the flow opened event ADL_FCM_EVENT_FLOW_OPENED will be received in the control handler. When some data is received on the subscribed port then data handler will be called to process data accordingly.
It should be noted that if COM1 is being subscribed for the FCM then run your Open AT application on some other port.
Thanks.