Some remarks about the software (Openflexure Pi OS and openflexure-connect)
The BOM suggests using a wireless keyboard with a built in trackpad. But this is not possible with the current configuration because bluetooth is broken. When trying to add a bluetooth device the list remains empty:
When I run the Pi 4B with the latest official Pi OS (Bookworm) there’s no problem connecting to bluetooth devices. Therefore the hardware seems ok. I also successfully tried with the latest Buster Raspi OS from 2021-05-28. Also with this version all available devices are visible. It even suggests connecting to our dishwasher on the lower floor :- )
It’s the same os with the same kernel as used by “Raspbian OpenFlexure”. I didn’t found the root cause of this error (yet, probably some incompatibility with the UART used by sangaboard), but it’s not a real problem. You could add a USB connected keyboard although being out in the field it isn’t very convenient to fiddle around with external devices, moreover when they are cabled…
Since the design uses a touch screen we already have a mouse. For the rare occasions when you have to enter text - like setting a filename for your saved captures - you just use a virtual keyboard on the touch screen (after all you use such a thing regularly on your smartphone ;- )
There are several of them, I use onboard.
To install it withyout a physical keyboard you have to remotely access you pi by using ssh. If you didn’t enable ssh access when flashing your sd card you can do it with the configuration app on the desktop:
Select the interfaces tab and enable ssh.
After connecting to your raspi just enter on the command line:
sudo apt install onboard
You can now start it from the raspi menu
Display configuration
The design uses a 7" monitor. These displays usually have a resolution of 1024 x 600. Unfortunately this specific resolution is not a selectable option in the screen configuration settings. If you select one of the available options like 1024 x 768 then the camera’s image on your screen is badly distorted. If you select 1920 x 1080 then the distorsion is minimized but text is too small and hardly readable. Furthermore the touch interface of the screen reacts very imprecise in this mode.
To configure this correctly you have to manually edit the file /boot/config.txt
You can do this again on the command line. If you are not comfortable with this you can also edit the file directly on the sd card while it is attached to your laptop.
Add these 3 lines to /boot/config.txt:
hdmi_cvt=1024 600 60 3 0 0 0
hdmi_group=2
hdmi_mode=88
Now your screen looks as it should.
One last enhancement. When you start OpenFlexureConnect you always get bored with the message on “what do you want to do” with the executable script.
To once and for all let it know that you want to execute the script you can set this “switch” in the settings of file manager. Open the file manager, go to menu → Edit → Preferences and put a checkmark at “Don’t ask…”
Now it won’t ask again :- )