Crash

Although I don't know what's the exact purpose the fflush function, it seems your tasks have no idle/sleep status; I mean they continuously rush in switching from one to the other at the maximum possible speed allowed by the scheduler.

IMHO this can generate two issues:

1. jtag allows a rather slow throughtput; the huge amount of output traffic generated by this relay race among tasks can easily choke the interface and affect the operation of the whole system

2. as I said in the previous post, the intrinsic absence of sleep instructions or significative execution times, will also make higher priorities tasks to immediately fall in the pending state, even before the lower priority one. In such a situation you could have inversion of the expected flow and possibly overlapped messages.

If tasks are actually not required to switch at that incredible rate, a possible solution would be to insert a TK_SLEEP(ticks) instruction between the cout print and the next OSSemPost.

A few ticks delay will ensure tasks to sequence in the correct order.

A better solution would be implementing a 3 state machine in a single task, if your complete project allows it; now I can't see the point in running 3 tasks if only one runs at a time.