performancepreempt-rt kernelraspberry pi 4braspbian busterreal time system
The Preempt-RT patching article is one of the most visited articles in my blog. However, that article needed a small update: Raspberry Pi 4B is out there and with Raspbian Buster, a new version of kernel is available: 4.19.y.
I also uploaded the compiled and patched kernel to lemariva/RT-Tools-RPi. You can follow all these steps and compile the kernel by yourself or you can download the files from the repository and deploy the kernel on your Raspberry Pi 4B.
This tutorial is the second of a serie of three that evaluate the performance of the Raspberry Pi 4B. This time the performance of the st...
anniversarybanggooddealse-ink displaypythonraspberry pi
Last week, I published an article about the Raspberry Pi and an e-ink display:
- #Raspberry Pi: an E-Paper display with Widgets (see Fig. 1a).
This time, this tutorial is about processing and displaying images on the 7.5" e-ink screen as shown in Fig. 1b.
Fig. 1a: E-ink Screen connected to a RPi
Fig. 1b: Banggood's 13th anniversary
original image here
Hardware & Software
You find here a list of hardware and software that you could use for this tutorial:
Raspberry Pi | 4 min | 6164
benchmarkbusterjupytern-queens problemperformanceraspberry pi 3 B plusraspberry pi 4braspbian
The new Raspberry Pi 4B has a lot of upgrades and one of the most important ones is the RAM: You can choose between three models (1GB, 2GB and 4GB). But, another main change is the CPU and the RAM bus: they changed from a Cortex-A53 64-bit (3B+/3A+) to a Cortex-A72 64-bit, both ARMv8, and from LPDDR2 SDRAM to LPDDR4 SDRAM. Thus, the CPU clock was increased to 1.5GHz (0.1GHz more) and the memory frequency to 2...
Raspberry Pi | 7 min | 8184
e-ink displaygoogle apisgoogle calendarraspberry piraspberry pi zerowaveshare
E-paper or e-ink displays are becoming more common in recent days. You can find them e.g. on readers, clocks and sensors. Thus, I looked for an e-ink display for the Raspberry Pi and I found the Waveshare® 7.5" E-ink Screen.
There are many projects with an e-ink display and the Raspberry Pi, but I first tried with an ESP32 and MicroPython. That solution didn't work (something was not working with the reset voltage - too much signal noise). So, that remains a work in progress and I will use this board. But now, in this tutorial, I uploaded a solution for the Raspberry Pi.
Fig. 1: Wa...
aqaraaqara sensorsdoor sensorhome assistantmqttpirraspberry pixiaomi gatewayxiaomi sensorszigbee
Last April, I published a tutorial about connecting the Aqara sensors to a Raspberry Pi without using the Xiaomi Gateway. To make that possible, I needed a CC Debugger to flash the TI CC2531 Zigbee Dongle. This debugger was used only one time, and then the Zigbee-USB dongle worked without any problem.
In this article, I will cover a way to flash the CC2531 without the CC Debugger. This reduces project costs (about $10 for debugger + cable adapters) and waiting time. Usually, you wait 30 days to get a low cost version of the debugger (using the cheapest shipping option). Let's start!
Raspberry Pi | 2 min | 4817
board brokencapacitor brokenquality control failedquality problemsraspberry piraspberry pi 4btantalum capacitor
On July 4th, I ordered a Raspberry Pi 4B. To be honest, I really didn't/don't need a new Raspberry Pi, I don't have any specific task for it, but I saw some cool stuff on the Internet, and I said: Ok, I need one! Thus, I bought the 4GB model on Reichelt. The expected delivery date was on July 10th but, I had to wait a little longer and I got it on July 17th! Everything was ok, and I got the following closed and sealed box (see Fig. 1):
Fig. 1: Box of the Raspberry Pi Model 4B (4GB RAM)
But, as soon as I opened the box, my joy faded! :( With a quick visual control, I checked tha...
aqaradockerhass.iohome assistanthome automationproduct reviewraspberry pi 3 B plusxiaomi gatewayxiaomi sensors
I've been very busy the last weeks. I moved to a new apartment and I was living between moving boxes. Four days ago, I managed to put my desk together and now I have some time (not a lot) to write a new article.
Last month I've received from GearBest two Aqara sensors:
These sensors use Zigbee and I connected them to a Raspberry Pi running Raspbian OS and a dockerized version of Home Assistant (DIY tutorial). This connection was made without using any Xiaomi gateway (DIY tutorial).
Hardware and Software...
Raspberry Pi | 4 min | 3772
coralcoral usb acceleratordockeredge-tpumachine learningraspberry piteachable machinetensorflow lite
Last week, the Coral team released updates to the Coral platform to "address customer feedback and make it easier to use the products and tool-chain". The Python API has now the ability to run multiple models in parallel, using multiple Edge TPUs.
Thus, due to the multiple changes, I updated the Docker image
lemariva/raspbian-edgetpuwhich includes the Edge-TPU libraries for Raspberry Pi 3 B+, Jupyter Notebooks and some other interesting libraries (check the Dockerfile).
Fig 1: Coral USB Accelerator, Jupyter and some training objects
The base Docker image remained
dockerembeddedhass.iohome assistanthome automationraspberry pisensorsxiaomizigbee
Last week, I published an article about using Xiaomi sensors without a Xiaomi Gateway. The gateway/hub can be replaced with a Raspberry Pi and a USB-ZigBee dongle. You find the instructions here: #ZigBee: Xiaomi Sensors using Raspberry Pi (without Gateway!).
As you can read in that article, two repositories are available to connect and process the data from the Xiaomi sensors. Additionally, Zigbee2mqtt can be connected to Hass.io. Well, I didn't want to use HassOS (the OS on which hass.io runs), but I wanted to use Hass.io running on Raspbian, otherwise with Home Assistant running as an appli...
aqaradoor sensorhome assistanthome automationmqttpirraspberry pixiaomi gatewayxiaomi sensorszigbee
This is what I will try to accomplish in this tutorial:
- Flash the USB-Zigbee Dongle with the correct FW
- Install a broker to connect to the sensors
- Configure the sensors using the broker
Xiaomi sensors use Zigbee for the connection which means we need some extra components to connect to them. This is the list of needed hardware:
Wireless Zigbee CC2531 x1 SmartRF04EB (**) x1 Debugger Ca...