← HomeThe person with the questions

Sreekar

I like electronics, small experiments, and finding out how the pieces fit. I write about electronics, code and what I learn while building things.

NOTE
Kindred Hands

The instructions are where the choice gets interesting

There were real choices in the Kindred Hands software journey. I looked at the initial WordPress and Dokan route, the continuing costs changed the direction, and I brought a couple of open-source alternatives together with guidance. The wider project also included research, evaluation and integ

·3 min read
NOTE
TinyML

A prediction is the end of the route, not the whole project

The voice project ends each processing pass with OFF, ON or noise, but the prediction is only the last visible part of the route. The export expects 16,000 raw samples at 16 kHz and uses a 650-value feature representation for three classes. The application has to supply that input before the mo

·4 min read
NOTE
Kindred Hands

Free to download, still my responsibility

The reason for comparing costs came from the purpose of Kindred Hands. I wanted a direct route to customers without our taking commission, and the initiative was intended as not-for-profit. Continuing costs around the first software route led me to explore alternatives. The purpose and the comm

·3 min read
NOTE
TinyML

What the battery would have to power between predictions

The classifier is only one part of what a battery would power. The application collects a complete audio frame, processes it, prints timings and class probabilities, then waits for one second. The code's delay does not put the controller into a documented sleep mode, and the application does no

·4 min read
NOTE
Kindred Hands

A feature list is very good at distracting me

My work on Kindred Hands included the e-commerce platform and multi-vendor functionality. The wider project also involved research and integration of virtual try-on. Those are different kinds of work, and I find them more useful to explain separately than to collect under the word advanced. Int

·3 min read
NOTE
Kindred Hands

The bill that comes back later

Running costs were one of the reasons I changed the first route considered for Kindred Hands. That made the question of what continues later much more practical. A service might be easy to choose at the beginning, while the reason for that choice becomes harder to explain once other work takes

·3 min read
NOTE
TinyML

I can calculate 46.3 millijoules. What did those millijoules do?

I recorded 14.04 mC at a 3.3 V supply over a 257.8 ms inference window. Multiplying the charge by the supply voltage gave 46.332 mJ, or about 46.3 mJ per inference. I checked the calculation against the average current and duration before writing the result down.

·4 min read
NOTE
Kindred Hands

The first price is only the beginning

The continuing costs around the first route changed the direction of my Kindred Hands setup. I had looked at WordPress and Dokan, then explored open-source alternatives and linked the chosen pieces with support. The cost question did more than send me looking for a lower price. It changed what

·4 min read
NOTE
Converters

I can finally ask a better question than “which one is better?”

I can now give a more useful answer than one winning converter name. The XL4015 and MP2307DN are commercial chips with different off-state paths and nominal switching frequencies. The XL4015 example uses an external diode; the MP2307DN controls a low-side MOSFET. I can follow that difference th

·3 min read
NOTE
Kindred Hands

WordPress, Dokan, and the jobs behind the names

WordPress and Dokan were part of the initial route I looked at for the multi-vendor side of Kindred Hands. They gave me something concrete to investigate. Instead of imagining one website that somehow handled everything, I could begin asking which part managed content, which part handled vendor

·3 min read
NOTE
Power meter

A useful reference is still a different circuit

The reference drawing and the ADS1115 program follow different routes. The drawing names ESP-WROOM-32, takes the sensor signals into the controller's ADC inputs and shows I²C serving an LCD. The application reads an external ADS1115 over I²C instead. I find the comparison useful because the pur

·4 min read
NOTE
Kindred Hands

One order is already asking a lot of questions

Kindred Hands was intended to help weavers sell more directly to customers without our taking commission. My technical responsibilities included the e-commerce and multi-vendor side of the initiative, with support. That made the route after a product page part of my responsibility too. A photog

·4 min read
NOTE
TinyML

The code has started drawing a current graph

The PPK2 views show two different electrical windows at a 3.3 V source setting. The wider view covers 10 seconds, with 50.13 mA average current, 87.10 mA maximum and 0.50 C of charge. The closer view covers 257.8 ms, with 54.44 mA average, 87.85 mA maximum and 14.04 mC. The time boundary is par

·4 min read