Research and Implementation of Periodic Real-Time Task Scheduling Mechanism Based on FORTH

Currently, Forth real-time systems are a research focus in the field of stack processors. Significant progress has been made, but in cases involving multiple periodic real-time tasks, instances of missed deadlines can occur. Additionally, there are issues with suboptimal allocation of task stack space resources in memory management. To address the characteristics of the Forth language using the stack as a channel, the LLF (Least Laxity First) task scheduling algorithm and a clock-interrupt-based preemptive scheduling algorithm are employed to implement a Forth-based periodic task scheduling mechanism. This mechanism introduces a dynamic priority calculation based on runtime and deadline, as well as dynamic allocation of task stack memory. Experimental results indicate that the current Forth task scheduling mechanism, compared to the previous Forth scheduling mechanism, is able to schedule multiple periodic real-time tasks without missing deadlines on a stack processor simulator, and it dynamically reclaims memory space used by tasks.