Support RPM filtering?

Started flying FPV in October 2020 but have since then blown a couple of ESC. And each time I’m going to setup the new ones I ran into problems so this time I write down some notes to not have that happen again…

The most common problem I run into is that I turn on Bi-directional DShot in BetaFlight but then I get RPM_FILTER Disarm disabled flag turned on!! And cannot figure out why??

The answer and solution is quite simple. The default ESC firmware does not support bidirectional DShot! And this article describes how to get it. The ESCs I have one need to use BLHeli_S firmware. On my Nazgul 5 2 HD the ESC has the G H 30 configuration and currently I’m using version 16.73. So I download the G_H_30_REV16_73.HEX firmware and use BLHeli Configuration to flash it. Other versions can be downloaded from 

Installing Xiaomi XiaoFang with OctoPrint

I wanted to have a live video stream from my Snapmaker 2.0 since it now has got a space in a closet. After a couple of tries to use a live video stream from the XiaoFang camera I realized it would not be a good solution. Quite a lot of tweaking to get it to work and it would require quite some resources from the Raspberry and thus might affect prints. But I still wanted to use that camera since I already had it.
OctoPrint video

After looking through the OctoPrint forum I saw that some people had used a special firmware on Wyze cameras to just make them into webcameras and connect directly to the Raspberry. The Wyze camera and the XiaoFang are the same camera, but wonder if it would just work to use that firmware? Found an article indicating it should work so gave it a try. Went to the firmware page and followed the instructions. Built a USB A to USB A cable and connected the camera to my PC. Wow, it is a webcam! Connected it the the Raspberry and entered the default settings for camera. Voila!

Xiaomi XiaoFang T20(or rather T20L)

Last summer I got a Xiaomi XiaoFang 1S camera from Magnus. Tried to get it working then but never succeeded but today I got some inspiration and managed to get it working and stream video over RTSP! It was not so hard. Just go to the GitHub project Xiaomi-Dafang-Hacks and follow the instructions but one must know that it was a T20L so start with those specific instructions.

One thing also that might have made a difference, now this time I did this on my Windows machine and not my Mac. And really made sure the SD card was formatted as a FAT32 drive.

 Also found this firmware that looks interesting; OpenMiko

Let’s Encrypt auto renew only fails for the server domain

I had a bit of struggle with Let’s Encrypts certbot today. Somehow it got 403 Forbidden each time it tried to authenticate the domain for my server. All the other website it worked without problem.

I created a simple text file in /.well-known/acme-challenge to see if I could access it. Yes it worked externally but then I realized I got 403 Forbidden when I tried to access from the server!

After lots of digging and testing I checked the apache general error.log and saw these lines:
[Sun Jan 20 21:52:32.754574 2019] [authz_core:error] [pid 2238] [client 2001:4b98:dc2:47:216:3eff:fe9b:cec6] AH01630: client denied by server configuration: /var/www/

Seeing that IPv6 address gave a clue and soon I found out it was due to that my webserver is not setup to listen to IPv6.
<virtualhost [2001:4b98:dc2:47:216:3eff:fe9b:cec6]:80>

Adding it to the Virtual host listen config it solved it!

Spela Spotify på Amazon Echo

Lånade hem en Amazon Echo för att experimentera lite vad man kan göra med den och se hur bra röstgränssnittet är. Någon hade nämnt man kan använda den för att spela musik från Spotify och hittade rätt fort var man skulle ställa in det men valet var utgråat!! Gick inte välja. Varför?

Efter lite googlande hittade jag att det beror på att ens Amazon konto är registrerat i fel region. Men hur ändrar jag och vad är rätt?

Den här artikeln gav tillräckliga ledtrådar för att inse var man ändrar det. Dock enklast är att först lägga in en ny USA adress(det är den region som du måste valt för att få upp Spotify valet visade det sig). Men vilken adress skall man fylla i? Random addresses ger ett par slumpmässiga men dessa ville inte Amazon acceptera. Jag tog dock ett av resultaten och klippte in i Google Maps och sedan klicka på en annan del av gatan för att få en giltig adress.

Sedan nästa steg var att göra som beskrivs i artikeln, klicka där det står Hello, Karl-Petter(ditt namn) och sedan välja Your Content and Devices. I artikeln står det att den heter Manage your Content and Devices men den heter Your Content and Devices numera. Sedan är det bara följa instruktionerna och välja din nya USA adress. Sedan får du vänta ett tag innan din Echo har fattat att du bytt region. Sedan är det bara följa denna guide.

Upgrading postgres version

Suppose you made a brew upgrade and postgres got upgraded. Follow then these steps to upgrade your old DB data to the new version.

Start to move of your old data directory:
mv /usr/local/var/postgres /usr/local/var/postgres_96_20171110

Initialize a new fresh DB with the new version of postgres
initdb /usr/local/var/postgres/

Check which postgres services are running and stop all
brew services list

Stop all postgres services, one command for each:
brew services start postgresql

Run postgres upgrade tool(-b and -B are the bin directories for old and new version, and -d and -D same for data directories):
pg_upgrade -b /usr/local/Cellar/postgresql\@9.6/9.6.6/bin/ -B /usr/local/Cellar/postgresql/10.1/bin/ -d /usr/local/var/postgres_20171110 -D /usr/local/var/postgres

Start the postgres service again:
brew services start postgresql