The ESP32-S3 supports the following maximum speeds on the SPI peripheral:
- As SPI master:
80 MHz - As SPI slave:
60 MHz
Note that the same clock speeds work for dual and quad SPI
Source: ESP32S3 datasheet,
17
Jul
2023
Allgemein
11
Jul
2023
How to install Syncthing on Ubuntu
sudo curl -s -o /usr/share/keyrings/syncthing-archive-keyring.gpg https://syncthing.net/release-key.gpg echo "deb [signed-by=/usr/share/keyrings/syncthing-archive-keyring.gpg] https://apt.syncthing.net/ syncthing stable" | sudo tee /etc/apt/sources.list.d/syncthing.list sudo apt -y install syncthing
04
Mar
2023
How to read length-prefixed binary message from Serial using Arduino
The following function allows you to read a binary message, prefixed by a single length byte, from Serial:
#include <Arduino.h>
void setup() {
Serial.begin(115200);
}
void HandleMessage(String msg) {
// TODO: Your code to handle the message goes here.
// See https://techoverflow.net/2022/11/15/how-to-print-string-as-sequence-of-hex-bytes-in-arduino/
// for an example of how to print the message as a sequence of hex bytes.
}
void ReadMessageFromSerial() {
// Wait until the length byte is available on Serial
while (Serial.available() == 0);
// Read the length of the message
int length = Serial.read();
// Read the rest of the message
String message = "";
for (int i = 0; i < length; i++) {
while (Serial.available() == 0);
message += char(Serial.read());
}
// Handle the message
HandleMessage(message);
}
void loop() {
ReadMessageFromSerial();
}
28
Jan
2023
How to fix InvenTree remote_image: Downloading images from remote URL is not enabled
Problem:
While trying to create an InvenTree object using a remote_image URL, you see an error message like
requests.exceptions.HTTPError: {'detail': 'Error occurred during API request', 'url': 'https://inventree-test.mydomain.com/api/company/', 'method': 'POST', 'status_code': 400, 'body': '{"remote_image":["Downloading images from remote URL is not enabled"]}', 'headers': {'AUTHORIZATION': 'Token 6daae3817756e9c1a3603b14d9582e61f50db388'}, 'params': {'format': 'json'}, 'data': {'name': 'DigiKey', 'website': 'https://www.digikey.de/', 'remote_image': 'https://logodix.com/logo/1667872.jpg', 'description': '', 'is_manufacturer': False, 'is_supplier': True, 'is_customer': False, 'currency': 'EUR'}}
Solution:
Open the InvenTree webinterface, open Server Configuration on the left
and enable Download from URL.
The setting will be effective immediately. There is no need to click any Apply button or restart the server.
08
Dec
2022
How to fix zincati not updating CoreOS: rpm-ostree deploy failed: error: Packages not found: …
Problem:
My zincati service – the service that automatically updates CoreOS could not update CoreOS due to the following logs (view with journalctl -xfu zincati.service):
[ERROR zincati::update_agent::actor] failed to stage deployment: rpm-ostree deploy failed:
error: Packages not found: magic-wormholeSolution:
The solution typically involves uninstalling the package – in this case magic-wormhole using
sudo rpm-ostree uninstall magic-wormhole
Note that this might uninstall a service that is required for your infrastructure, and it will delete files associated with the package in the process of uninstalling it. You should make a backup of valuable data in any case.
21
Sep
2022
How to prevent redmine always logging out
In Redmine, by default you are always logged out after a very short period of time.
You can fix this by logging in as an administrator and opening Administration -> Settings -> Authentication and setting Autologin to 365 days. You can also choose a lower value if you want sessions to automatically expire sooner.
27
Aug
2022
Python curses keycode to key mapping
The following mapping is helpful in order to determine the mapping of a keycode to the corresponding curses.KEY_... constant.
I extracted this mapping by using
import curses print(curses.__dict__)
Curses key mapping
'A_ATTRIBUTES': 4294967040, 'A_NORMAL': 0, 'A_STANDOUT': 65536, 'A_UNDERLINE': 131072, 'A_REVERSE': 262144, 'A_BLINK': 524288, 'A_DIM': 1048576, 'A_BOLD': 2097152, 'A_ALTCHARSET': 4194304, 'A_INVIS': 8388608, 'A_PROTECT': 16777216, 'A_CHARTEXT': 255, 'A_COLOR': 65280, 'A_HORIZONTAL': 33554432, 'A_LEFT': 67108864, 'A_LOW': 134217728, 'A_RIGHT': 268435456, 'A_TOP': 536870912, 'A_VERTICAL': 1073741824, 'A_ITALIC': 2147483648, 'COLOR_BLACK': 0, 'COLOR_RED': 1, 'COLOR_GREEN': 2, 'COLOR_YELLOW': 3, 'COLOR_BLUE': 4, 'COLOR_MAGENTA': 5, 'COLOR_CYAN': 6, 'COLOR_WHITE': 7, 'BUTTON1_PRESSED': 2, 'BUTTON1_RELEASED': 1, 'BUTTON1_CLICKED': 4, 'BUTTON1_DOUBLE_CLICKED': 8, 'BUTTON1_TRIPLE_CLICKED': 16, 'BUTTON2_PRESSED': 64, 'BUTTON2_RELEASED': 32, 'BUTTON2_CLICKED': 128, 'BUTTON2_DOUBLE_CLICKED': 256, 'BUTTON2_TRIPLE_CLICKED': 512, 'BUTTON3_PRESSED': 2048, 'BUTTON3_RELEASED': 1024, 'BUTTON3_CLICKED': 4096, 'BUTTON3_DOUBLE_CLICKED': 8192, 'BUTTON3_TRIPLE_CLICKED': 16384, 'BUTTON4_PRESSED': 65536, 'BUTTON4_RELEASED': 32768, 'BUTTON4_CLICKED': 131072, 'BUTTON4_DOUBLE_CLICKED': 262144, 'BUTTON4_TRIPLE_CLICKED': 524288, 'BUTTON5_PRESSED': 2097152, 'BUTTON5_RELEASED': 1048576, 'BUTTON5_CLICKED': 4194304, 'BUTTON5_DOUBLE_CLICKED': 8388608, 'BUTTON5_TRIPLE_CLICKED': 16777216, 'BUTTON_SHIFT': 67108864, 'BUTTON_CTRL': 33554432, 'BUTTON_ALT': 134217728, 'ALL_MOUSE_EVENTS': 268435455, 'REPORT_MOUSE_POSITION': 268435456, 'KEY_BREAK': 257, 'KEY_DOWN': 258, 'KEY_UP': 259, 'KEY_LEFT': 260, 'KEY_RIGHT': 261, 'KEY_HOME': 262, 'KEY_BACKSPACE': 263, 'KEY_F0': 264, 'KEY_F1': 265, 'KEY_F2': 266, 'KEY_F3': 267, 'KEY_F4': 268, 'KEY_F5': 269, 'KEY_F6': 270, 'KEY_F7': 271, 'KEY_F8': 272, 'KEY_F9': 273, 'KEY_F10': 274, 'KEY_F11': 275, 'KEY_F12': 276, 'KEY_F13': 277, 'KEY_F14': 278, 'KEY_F15': 279, 'KEY_F16': 280, 'KEY_F17': 281, 'KEY_F18': 282, 'KEY_F19': 283, 'KEY_F20': 284, 'KEY_F21': 285, 'KEY_F22': 286, 'KEY_F23': 287, 'KEY_F24': 288, 'KEY_F25': 289, 'KEY_F26': 290, 'KEY_F27': 291, 'KEY_F28': 292, 'KEY_F29': 293, 'KEY_F30': 294, 'KEY_F31': 295, 'KEY_F32': 296, 'KEY_F33': 297, 'KEY_F34': 298, 'KEY_F35': 299, 'KEY_F36': 300, 'KEY_F37': 301, 'KEY_F38': 302, 'KEY_F39': 303, 'KEY_F40': 304, 'KEY_F41': 305, 'KEY_F42': 306, 'KEY_F43': 307, 'KEY_F44': 308, 'KEY_F45': 309, 'KEY_F46': 310, 'KEY_F47': 311, 'KEY_F48': 312, 'KEY_F49': 313, 'KEY_F50': 314, 'KEY_F51': 315, 'KEY_F52': 316, 'KEY_F53': 317, 'KEY_F54': 318, 'KEY_F55': 319, 'KEY_F56': 320, 'KEY_F57': 321, 'KEY_F58': 322, 'KEY_F59': 323, 'KEY_F60': 324, 'KEY_F61': 325, 'KEY_F62': 326, 'KEY_F63': 327, 'KEY_DL': 328, 'KEY_IL': 329, 'KEY_DC': 330, 'KEY_IC': 331, 'KEY_EIC': 332, 'KEY_CLEAR': 333, 'KEY_EOS': 334, 'KEY_EOL': 335, 'KEY_SF': 336, 'KEY_SR': 337, 'KEY_NPAGE': 338, 'KEY_PPAGE': 339, 'KEY_STAB': 340, 'KEY_CTAB': 341, 'KEY_CATAB': 342, 'KEY_ENTER': 343, 'KEY_SRESET': 344, 'KEY_RESET': 345, 'KEY_PRINT': 346, 'KEY_LL': 347, 'KEY_A1': 348, 'KEY_A3': 349, 'KEY_B2': 350, 'KEY_C1': 351, 'KEY_C3': 352, 'KEY_BTAB': 353, 'KEY_BEG': 354, 'KEY_CANCEL': 355, 'KEY_CLOSE': 356, 'KEY_COMMAND': 357, 'KEY_COPY': 358, 'KEY_CREATE': 359, 'KEY_END': 360, 'KEY_EXIT': 361, 'KEY_FIND': 362, 'KEY_HELP': 363, 'KEY_MARK': 364, 'KEY_MESSAGE': 365, 'KEY_MOVE': 366, 'KEY_NEXT': 367, 'KEY_OPEN': 368, 'KEY_OPTIONS': 369, 'KEY_PREVIOUS': 370, 'KEY_REDO': 371, 'KEY_REFERENCE': 372, 'KEY_REFRESH': 373, 'KEY_REPLACE': 374, 'KEY_RESTART': 375, 'KEY_RESUME': 376, 'KEY_SAVE': 377, 'KEY_SBEG': 378, 'KEY_SCANCEL': 379, 'KEY_SCOMMAND': 380, 'KEY_SCOPY': 381, 'KEY_SCREATE': 382, 'KEY_SDC': 383, 'KEY_SDL': 384, 'KEY_SELECT': 385, 'KEY_SEND': 386, 'KEY_SEOL': 387, 'KEY_SEXIT': 388, 'KEY_SFIND': 389, 'KEY_SHELP': 390, 'KEY_SHOME': 391, 'KEY_SIC': 392, 'KEY_SLEFT': 393, 'KEY_SMESSAGE': 394, 'KEY_SMOVE': 395, 'KEY_SNEXT': 396, 'KEY_SOPTIONS': 397, 'KEY_SPREVIOUS': 398, 'KEY_SPRINT': 399, 'KEY_SREDO': 400, 'KEY_SREPLACE': 401, 'KEY_SRIGHT': 402, 'KEY_SRSUME': 403, 'KEY_SSAVE': 404, 'KEY_SSUSPEND': 405, 'KEY_SUNDO': 406, 'KEY_SUSPEND': 407, 'KEY_UNDO': 408, 'KEY_MOUSE': 409, 'KEY_RESIZE': 410, 'KEY_MIN': 257, 'KEY_MAX': 511}
19
Aug
2022
How to setup ZeroTier One & ZTNCUI using docker-compose in just 2 minutes
First, create a directory for the ZeroTier One / ZTNCUI files to reside in, e.g.:
mkdir /opt/zerotier-mydomain
Now, create docker-compose.yml in that directory
version: '3.4'
services:
ztncui:
container_name: ztncui
restart: always
image: keynetworks/ztncui
ports:
- 9993:9993/udp
- 3180:3180
- 3443:3443
volumes:
- ./etc:/opt/key-networks/ztncui/etc
- ./zt1:/var/lib/zerotier-one
After that, create .env in said directory containing some info about your node:
NODE_ENV=production HTTPS_PORT=3443 MYDOMAIN=zerotier.mydomain.com
Now we’ll use the script from Create a systemd service for your docker-compose project in 10 seconds in order to create a systemd service to automatically run the service:
curl -fsSL https://techoverflow.net/scripts/create-docker-compose-service.sh | sudo bash /dev/stdin
This script will also automatically start the service (i.e. docker-compose up). ZTNCUI (which comes packaged with ZeroTier One) will generate a temporary admin password automatically, which we can extract from the log using this simple command:
docker-compose exec ztncui cat /var/log/docker-ztncui.log | grep "Current Password" | tail -n 1
Example output:
2022/08/19 14:32:37 Current Password: esh0Eengai
Be sure to open the ports 9993/udp, 3180 and (unless you are using a reverse proxy) 3443 in your firewall, for example:
sudo ufw allow 9993/udp sudo ufw allow 3180 sudo ufw allow 3443
Now we can open https://[IP]:3443 to open the webinterface (ignore the certificate validation error). You can also setup a reverse proxy at this stage, which we’ll cover in future posts.
You should see a page like this one:
Click Login at the top right:
Enter admin as username and the password we extracted above (esh0Eengai in this example).
You will be asked to change your password, and after that you can create ZeroTier networks.
31
Jul
2022
Where to find ESP32S2 bare chip reference schematic?
If you are not using the ESP32S2 as a module but as a chip, you need a reference schematic to check if you have errors in a schematic.
A good place to start is by checking out the schematic of the ESP32S2-MINI, which you can find on page 19 & 20 of the module datasheet.
22
Jul
2022
How to import mbox file in Thunderbird
- Install ImportExportTools NG
- Right click on Local folders and in the context menu, in the ImportExportTools NG menu, click on Import mbox file
22
Jul
2022
How to add filename extension to every file in directory
This shell script will rename every file in a directory recursively and add a .docx extension to its filename (even if there is already an extension), preventing overwriting existing files of the same name via mv --backup=numbered:
find . -type f -exec mv -v --backup=numbered "{}" "{}.docx" \;
03
Jun
2022
How to configure SMTP server on MikroTik RouterOS
Use the following command in order to configure SMTP settings for a MikroTik router:
/tool e-mail set address=smtp.mydomain.com from="MikroTik <[email protected]>" tls=starttls [email protected] password=uFoome0Noh
Alternatively, you can configure these settings directly on the web interface at WebFig => Tools => EMail.
27
May
2022
SSH to LXC container with Pubkey
ssh [user]@[my-container-address]
Problem
[user]@[my-container-address] Permission denied (publickey).
Solution
Change the sshd_config
vim /etc/ssh/sshd_config
from this
# PubkeyAuthentication no
to this
PubkeyAuthentication yes
.
Do not forget to add your pubkey to your authorized keys.
mkdir /home/[myuser]/.ssh & vim /home/[myuser]/.ssh/authorized_keys
27
May
2022
LXC container share host network
Goal
You want to share the host network with all your lxc containers.
Check network settings of your containers by typing:
lxc network list
If it displays something like that:
+---------+----------+---------+-------------+---------+ | NAME | TYPE | MANAGED | DESCRIPTION | USED BY | +---------+----------+---------+-------------+---------+ | docker0 | bridge | NO | | 0 | +---------+----------+---------+-------------+---------+ | eth0 | physical | NO | | 0 | +---------+----------+---------+-------------+---------+
Solution
Set up your container with the default settings of LXD, creating a network for all containers attached to the newly created lxdbr0 adapter on the host system with
lxd init
and accept the defaults:
Would you like to create a new local network bridge? (yes/no) [default=yes]: What should the new bridge be called? [default=lxdbr0]:
and have your containers already connected to the lxdbr0 bridge on your host.
You might now see something like this.
+---------+----------+---------+-------------+---------+ | NAME | TYPE | MANAGED | DESCRIPTION | USED BY | +---------+----------+---------+-------------+---------+ | docker0 | bridge | NO | | 0 | +---------+----------+---------+-------------+---------+ | eth0 | physical | NO | | 0 | +---------+----------+---------+-------------+---------+ | lxdbr0 | bridge | YES | | 5 | +---------+----------+---------+-------------+---------+
Now try it
lxc exec [mycontainer] /bin/bash
curl https://techoverflow.net
09
Feb
2022
OctoPrint: Pause/Resume G-Code to move nozzle away
This pause / resume G-Code for OctoPrint (will likely also work with other platforms, but we only tested using OctoPrint) will move the nozzle 100mm away from the part being printed during the pause and (after clicking resume) will move to the original position i.e. it will continue the print normally.
This is useful to prevent heat damage to the part and also allow you to clean the nozzle during pause
Pause G-Code:
G91 ; Set relative positioning mode G0Z100 ; Move Z up 100mm to assist nozzle cleaning G90 ; Set absolute positioning mode
Resume G-Code:
G91 ; Set relative positioning mode G0Z-100 ; Move Z down 100mm to return to print position G90 ; Set absolute positioning mode
02
Feb
2022
Excel: How to replace formula cell by its value
TL;DR: Press F2, then F9 to replace a cell by its value.
Click on the formula cell (click once, no need to click twice):
Now press the F2 key to edit the cell:
Now press the F9 key to replace the cell by its value:
23
Jan
2022
How to fix MANIFEST.in graft having no effect on Windows
Problem:
In your MANIFEST.in, you have a line like
graft src/
but when you run
python setup.py sdist
some file in src is not included in the archive
Solution:
This is due to the slash at the end of src/! The slash works fine on Linux, but on Windows, backslashes are used to separate directory names. You can just remove the slash after src, it doesn’t serve any purpose on Windows or Linux:
graft src
After that, retry and you should see your file being included in the sdist archive.
21
Jan
2022
Insurgency: Which RCON client should you use?
For most users, the in-game console is the best RCON client to use since you don’t need to install separate software and it has auto-complete features. See Insurgency: How to connect to RCON using the in-game console for a guide how to connect to RCON using said console.
21
Jan
2022
Insurgency: How to change map & gamemode using the console (RCON)
First, follow our guide on how to connect to RCON using Insurgency’s in-game console.
Now enter for example
rcon map sinjar hunt
to immediately switch the map & gamemode.
21
Jan
2022
Insurgency: How to connect to RCON using the in-game console
First, open the console using the configured hotkey (default: The key directly left of the 1 key). If that doesn’t work, remap the key in the settings.
Then enter
rcon_password "mypassword"
to set the password to connect to the RCON server.
Now you can use admin commands in the format
rcon <command>