5 participant "E20 main thread" as main
6 participant "tdm thread" as sub
8 sub <-- : a synchronous event
10 --> main: a synchronous event
12 sub -> sub: calling thread callbacks in tdm-thread
15 sub --> main: sending a synchronous event
16 sub -> sub: pthread_cond_wait
18 main -> main: calling thread callbacks in main-thread
21 main --> sub: sending a synchronous event
22 main -> main: pthread_cond_wait
29 ... <color #red>(DEADLOCK)</color> ...