Composite STM-1 and Channalised STM-1

Hello
Would you kindly correct me
composite STM-1 is a 155Mbps and a channalised STM-1 is a 155Mbps made up of 63 E1s. I want to know from a Composite STM-1 can I be able to terminate only 16 E1s on a media gate way. I am using Ericsson MGW R6. but with channalised STM-1 I can terminate 16 E1s since Channalised STM-1 is made up of 63 E1s. so is it possible to terminate 16 E1s or use 16 E1s from a composite STM-1 or I need a channalised STM-1 to use 16 E1s