I will show a solution in two steps using systemd-networkd. First I create an access point (wlan0) and bridge it with the wired connection (eth0). Then I configure routing between the bridge (br0) and the up-link (eth1).
For reference I use Raspbian Stretch Lite 2019-04-08 updated with sudo apt update && sudo apt full-upgrade && sudo reboot ...
To determine what your program is doing, you need to save the output of the program to a file. Use this type of call to start the program
/path/to/script >> /path/to/log/file 2>&1 &
This will start the program in the background, and send all output (both stdout and stderr) to a file of your choice.
Keep in mind that if the script is long ...
You are using an experimental kernel and presumably firmware, probably from running rpi-update. There are outstanding issues with the 4.19 kernel.
"In normal circumstances there is NEVER a need to run rpi-update as it always gets you to the leading edge firmware and kernel and because that may be a testing version it could leave your RPi unbootable". ...
There is no need to do much configuration when using an ethernet cable. With default Raspbian Stretch everything works out of the box. Just flash the image, and boot it on your RasPi. If there is a DHCP server running on the other side of the ethernet cable then the RasPi will get its configuration from it including an ip address. If there is no DHCP server ...
I'd be inclined to wonder why my WiFi was slow instead of Bluetooth. Just as a rough figure of merit, WiFi could be 300x faster than Bluetooth (ref).
And with respect to, 3 seconds to transfer a length 8192 integer sequence:
The ref indicates Bluetooth data rates can be as much as 2.1 Mbps, but also says there's a 200 msec latency. Could you be incurring ...
How can Rpi send text strings to HC05?
I once wrote a couple of python functions to do the following:
Reset HC05 to AT command mode,
Reset HC05 to connection mode,
Write AT command to HC05,
Read reply from HC05.
With these set of basic functions, I can then do the following.
Set HC05 to AT command mode
Would a microcontroller and a bit of Arduino code work for your use case instead of a passive IC?
I saw a similar challenge addressed in the openDog project, the youtube update featuring the hardware change can be seen at https://youtu.be/hxNLQ7qGlbg
In the openDog project there was a transition from using Arduino Mega boards that featured 4 serial lines (...