Changes made are:
- Use the time module in place of the pyb module for delays.
- Use spi.read/spi.write instead of spi.send/spi.receive.
- Drop some non-portable parameters to spi and pin initialization.
Thanks to @deshipu for the original patch.
Internal structure of k_fifo changed between 1.7 and 1.8, so we need
to abstract it away. This adds more functions than currently used, for
future work.
This allows to execute a command and communicate with its stdin/stdout
via pipes ("exec") or with command-created pseudo-terminal ("execpty"),
to emulate serial access. Immediate usecase is controlling a QEMU process
which emulates board's serial via normal console, but it could be used
e.g. with helper binaries to access real board over other hadware
protocols, etc.
An example of device specification for these cases is:
--device exec:../zephyr/qemu.sh
--device execpty:../zephyr/qemu2.sh
Where qemu.sh contains long-long qemu startup line, or calls another
command. There's a special support in this patch for running the command
in a new terminal session, to support shell wrappers like that (without
new terminal session, only wrapper script would be terminated, but its
child processes would continue to run).
Without this, if there's a large chunk of data coming from hardware (e.g.
clipboard paste, or fed programmatically from the other side of the console),
there's a behavior of initial mass fill-in of the buffer without any
consumption, which starts much later and doesn't catch up with further
filling, leading to buffer overflow.
MONO_xxx is much easier to read if you're not familiar with the code.
MVLSB is deprecated but kept for backwards compatibility, for the time
being.
This patch also updates the associated docs and tests.
This should be a little more efficient (since we anyway scan the input
packet for the interrupt char), and it should also fix any non-atomic read
issues with the buffer state being changed during an interrupt.
Throughput tests show that RX rate is unchanged by this patch.
Paul Sokolovsky
Damien George
Peter Hinch