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by TickleSteve 2660 days ago
If RTEMS is controlling the execution of your code, your running on or in RTEMS.

Direct hardware access isn't really "bare metal" in the same manner as software running in DOS is not bare-metal. direct-hardware access is provided in both.
1 comments
e_proxus 2660 days ago
RTEMS isn't "controlling" the execution of the code, it just supplies implementation for OS-specific utilities (effectively the POSIX API). The BEAM VM code is compiled to machine code and runs directly on the CPU. As peerst explained, if you write your own C code in an Erlang port driver for example, you don't have to use RTEMS at all.
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anonymousDan 2660 days ago
Is there the ability to run multiple OS processes or is the BEAM VM the only thing running after boot?
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e_proxus 2659 days ago
You can only run one process in RTEMS (hence the name The Real-Time Executive for Multiprocessor Systems), however you can simulate other processes via threads. This is how we run the network stack and Wi-Fi configuration tools among other things.
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