programming esp32-wrover with DHT22 (AM2302) humidity and temperature sensor

Posted on 2025-03-28 by einsamsoldat

Referring to the original material at ESP32 with DHT11/DHT22 Temperature and Humidity Sensor using Arduino IDE | Random Nerd Tutorials

The reference is straight forward; however, it is not for the esp32-wrover.

Based on the from the reference, using educated guess without reading the specification, it is a hindsight that the original wiring will not work.

Original wiring on the breadboard for the ESP32-wrover, spoiler this is wrong for many reasons

It didn’t work, was getting the error “Failed to read from DHT sensor!” from the sample code.

DHTPIN were used is 4, which I had wrongly assumed it to be the physical pin number. Little did I know that, the reference is referring to GPIO4 instead of the physical pin number.

Based on the reference, ESP32-wrover spec sheet page 9, the physical pin 4 is the SENSOR_VP.

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Preparing IoT projects for cheap

Posted on 2025-03-18 by einsamsoldat

IoT starter kit using the ESP32-WROVER-IE

I had recently embarked on a small project inspired by ex-colleagues. One of the largest obstacles for a hobbyist is the cost of starting an IOT project.

The project was reignited after encouraging from a friend. I am amazed after learning from him that I can get an arduino with wifi and BLE; ESP32-wrover-ie . The primary appeal is the module cost MYR32 (at the time of the blog post). Its price will be able to allow hobbyist like me to create IoT that will act as a DAQ (Data AQuisition) device, that I can use the data to try out weather forecast modelling using BiLTSM; that will be another story hopefully in near future.

The customed model kit bundle are as following:

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Making sure CUDA is installed in Jetson Nano

Posted on 2025-02-23 by einsamsoldat

Type in nvcc –version from your Jetson Nano terminal is the sure way.

If the nvcc is missing, it could mean that the jetson-toolkit were not installed, or the binaries was not added to your session.

To reassociate your user to installed nvcc

The commands to reassociate.

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Extending or upgrade the seeed reComputer J1020

Posted on 2025-02-18 by einsamsoldat

Part number used for the board in the seeed reComputer J1020 connecting to the nVidia Jetson SODIMM module is reComputer J202 – Carrier Board for Jetson Xavier NX/Nano/TX2 NX.

reComputer J202 Carrier Board for Jetson Xavier NX with compact function design and same size of NVIDIA® Jetson Xavier NX™ carrier board – Seeed Studio

Based on the spec sheet in the web site above, the J202 carrier board. Can be used to host the Jetson Xavier NX, Jetson Nano and Jetson TX2 NX.

Other than the Jetson Nano, any other Jetson module that is compatible with the J202 carrier board will requires a heatsink with active fan.

Recommended heatsink with active fan Manufacturer Part Number (MPN)s are as follows:

ATS-NVA-2781-C1-R0

114992687