This paper addresses the problem of scheduling periodic parallel tasks on a multi-resource platform, where tasks have real-time constraints. The goal is to exploit the inherent parallelism of a platform comprised of multiple heterogeneous resources. A resource model is proposed, which abstracts the key properties of any heterogeneous resource from a scheduling perspective. A new scheduling algorithm called PSRP is presented, which refines MSRP. The schedulability analysis for PSRP is presented. The benefits of PSRP are demonstrated by means of an example application showing that PSRP indeed exploits the available concurrency in heterogeneous real-time systems.