A method to define the semantics of programs written in real-time languages is developed for the language Mini CSP-R. It takes in account the communication between several processes, parallel commands and real- time problems. The meaning of Mini CSP-R commands is defined denotationally by relating the meaning of each construct to the meaning of its components. The authors compare their method with some another methods of defining the semantics. As an appendix, the paper contains the comparison of the languages Mini CSP-R and CSP-R. As another appendix, it points out the simulation of the languages ADA in CSP-R.