Restarting I2C when touchpad is not working

January 11, 2022 Reading time: ~1 minute

After I replaced the Clickpad of my Lenovo L440 with a touchpad (see https://mastodon.xyz/@nause_marc/107111989617471186) the Touchpad would not work occasionally under Debian when returning from suspend. I created a small script called restarti2c.sh with the following content:

sudo /sbin/rmmod i2c_i801 && sudo /sbin/modprobe i2c_i801

This restarts the I2C bus kernel module, which makes the touchpad work again. I run it whenever necessary.


Fixing failure of software upload to µController

December 5, 2019 Reading time: ~1 minute

If uploading software from the Arduino IDE or the commandline via avrdude to a microcontroller like an Arduino or an ESP8266 fails due to missing access rights ("Permission denied"), what helps is either

sudo chmod a+rw /dev/ttyUSB0

or adding the user to the group "dialout":

sudo usermod -a -G dialout theuser

See: https://forum.arduino.cc/index.php?topic=495039.0


Changing the RAM chip of the Super Snapshot V5

September 4, 2019 Reading time: 2 minutes

The manual of the Super Snapshot V5 mentions that the 8kB RAM chip of the cartridge can be upgraded to 32kB. Back in the days™ it was possible to send the cartridge to LMS Technologies. Nowadays this is not an option anymore and I was happy to find an article by Chris Kobayashi which describes the required steps. Since the article does not contain any illustrations, I decided to share some photos I took when I changed the RAM of my Super Snapshot V5.

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Re-soldering the reset button of the Super Snapshot V5

April 23, 2018 Reading time: 2 minutes

In an act of clumsiness I pulled off the cables connecting the reset button of my Super Snapshot V5 and the PCB. I asked Twitter and Mastodon for help, but to no avail. The search engine of my choice also did not come up with any helpful link. Luckily information about the Commodore 64 is all over the web. Read more