During revive the retro computer I discovered a problem with a Chieftec power supply: After powering it up it is emitting high frequency noise, mainboard is not starting after pushing the power button. I connected the multimeter and measured the STB (standby) line (violet color …
Read MoreJLCPCB and my new 1-wire bus master project
Hello,As you’ve probably seen (if you read my blog), my previous bus master was ugly, small and uncomfortable to use.It was the high time to make something new… 🙂 Connecting 1-wire buses should be as easy as connecting a LAN cable to the switch. As …
Read MoreUsing Rigol DS1074Z oscilloscope under Linux and PulseView
Hi,I recently bought a new Rigol DS1074Z which is a great oscilloscope for hobbyist. The feature to price factor was really great and it also has a quite nice reviews, so I decided to give it a try 🙂 Quick hardware overview It is a …
Read Morebinding/unbinding usb drivers a.k.a. who stole my hidraw1 device file
Hi! Recently I was playing with using my HID device differently then usual: I used the libusb library. Instead opening a raw file /dev/hidraw1, I used libusb_open_device_with_vid_pid(). Everything was working properly, then it was a time to go back using the hidraw file… but wait: …
Read MoreRaspberry Pi’s serial console
Hi! As I sometimes have odd behavior with my Raspberry Pi (the USB/LAN is stopping working, while the whole raspberry does still work), I had to find out the method to debug this specific problem. Connecting HDMI display and a keyboard in place where I …
Read Morebcm2835_i2c is the new i2c module on RPi kernels
Hello. Yesterday I’ve updated the kernel on my RPi from 4.4.11+ to 4.14.31+. Unfortunately the i2c stopped working despite the module bcm2708_i2c loaded. Trying to add the ds2482 with command: echo ds2482 0x18 > /sys/bus/i2c/devices/i2c-1/new_device gives ‘no such file or directory’ error. I reported this …
Read MoreHow to hack my own IP camera :)
Camera overview I have a cheap IP camera from Polish reseller (ivel.com.pl). It is in fact a IP cam based on HiSilicon SOC. Manufacturer code is:Â LV-IP22IR40DVBL and it is available here. In fact for this price the camera is quite nice. It has a solid …
Read MoreRPi: creating a RAM-disk running Linux environment from NFS booted Raspbian
Sometimes you need a very specific use case for your Raspberry Pi. The durability (and speed) of the SD card used in RPi may vary. Because of this I always tend to move Raspbian to an NFS share, and boot via NFS (root over NFS). …
Read MoreMonitoring Voltronic Power Axpert MEX inverter under Linux
I am using the SKYMAX Expert MEX 3K-24 inverter. In fact it is identical with Voltronic Power Axpert MEX 3K-24, it was just rebranded by a Polish company. It is a 24 volts model, so I am using a two 12V 100Ah batteries connected in …
Read MoreDS2438-based 1-Wire humidity sensor
In this post I want to share with you how I did the humidity measurement in my bathroom. Because I already have 1-Wire buses all over my house measuring temperatures (DS18B20), sensing my switches (DS2413) and controlling relays (DS2408), so logical step was to measure …
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