PrajnaEdge
A curiosphere for curious minds who want to understand, experiment with, and experience technology.

Technology is a system of connections.

Modern technology is built from layers that continuously interact with one another. At the physical level, electronic devices transform electrical signals into digital information. Digital logic turns that information into computation, while processors, memory and communication interfaces provide the machinery needed to execute instructions and move data. As these components become part of embedded systems, they begin to interact with the physical world through sensors, controllers, actuators and real-time software.

But computation does not exist in isolation. Operating systems coordinate hardware and software, firmware gives specialized machines their behaviour, and communication protocols allow independent systems to exchange information. At the same time, machine learning is moving beyond the cloud into edge and on-device systems, where models must operate within real constraints such as memory, processing power, latency and energy consumption.

PrajnaEdge explores these connections as one continuous technology landscape — and takes them beyond explanation. From computing foundations and embedded systems to intelligent machines and edge AI, ideas can be understood, experimented with, and eventually turned into technology that can be experienced in the real world.

To continue exploring
Products

Technology, made tangible.

PrajnaEdge products and technology experiences are currently in development.
In Development

Playground

Experiment with intelligence beyond the cloud.

AI inference performed closer to where data is generated — optimizing model representation to reduce latency, memory footprint, and bandwidth requirements.
Cloud AI Coming Soon

Model Training & Representation

Explore how neural networks learn representations from data before compression and deployment. Future experiments will allow adjusting learning parameters—such as learning rate, epoch counts, and batch sizes—to observe loss trajectories and decision boundaries.

Edge AI Computer Vision

Image Classification

Can this image classifier maintain its intelligence while becoming small enough for the edge?

On-device AI AI-Thinker ESP32-CAM

On-device Image Classification

Run a fully quantized INT8 image-classification model directly on embedded hardware.

Edge AI Playground

Image Classification

Can this image classifier maintain its intelligence while becoming small enough for the edge?

Choose an image

Upload an image
Supports JPG, JPEG, PNG
This classifier recognizes only Apple, Banana, and Orange. Other objects may be incorrectly classified as one of these classes.

Choose the model

Model size
4.91 MiB
Largest activation
~625 KiB
Test accuracy
99.11%
Measured model accuracy
Your image is processed locally in your browser.
On-device AI · Inference

On-device Image Classification

Run a fully quantized INT8 image-classification model directly on embedded hardware.

This experiment investigates preparing a compact INT8 TensorFlow Lite model for direct inference on resource-constrained embedded hardware. The model uses the same CNN architecture as the Edge AI exploration, converted to a full INT8 representation to classify three classes: Apple, Banana, and Orange.

Model size
1.23 MiB
INT8 quantized weights
Model accuracy
99.11%
Measured test accuracy
Target hardware
AI-Thinker ESP32-CAM
Embedded microcontroller target

Explore the ideas, systems and connections that shape technology — choose any node to begin your journey.

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Embedded Systems Tree
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PrajnaEdge Library

PrajnaEdge Library

Practical guides to embedded systems and engineering.

CAN Bus Debugging: From Symptoms to Root Cause Book Cover
Automotive · Embedded Protocol Debugging

CAN Bus Debugging: From Symptoms to Root Cause

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Edge AI Demonstrations

Deploying neural networks and intelligent decision loops on raw silicon targets.

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Coordination

When Machines Learned to Observe

How reality became numbers.

ADCSamplingQuantizationResolutionHardware Pipeline

1. The Analog World

The physical world is fluid, continuous, and unbroken. If you measure the temperature of a room, it does not jump instantly from 22°C to 23°C; it transitions through an infinite number of intermediate states. The pressure of sound waves hitting a microphone, the changing angle of a steering wheel potentiometer, the terminal voltage of a discharging lithium-ion battery, and the intensity of morning light are all continuous. They exist as physical quantities that can take any value within a range, changing smoothly across time.

Continuous physical waveforms vs discrete computer states
Continuous physical waveforms vs discrete computer states

2. Why Computers Cannot Directly Understand Analog Signals

A digital processor, by contrast, is a machine of absolute division. Inside its silicon core, electricity is gated into binary states: a transistor is either fully conducting or cut off, representing a logical 1 or 0. A processor cannot store 'a slightly warm voltage' or 'a loud sound wave' in its registers. It understands only precise digital numbers. To bridge this gap between continuous physical reality and discrete computation, the system needs an interface that translates raw, infinitely variable analog signals into finite, structured digital words. This interface is the Analog-to-Digital Converter (ADC).

3. Sampling: Freezing Time

The first step of this translation is Sampling. Since a computer cannot observe the world constantly, it must observe it at discrete moments. Sampling is the process of reading the analog voltage of a signal at precise, regular intervals.

This is where we connect back to the Hardware Timer. A timer serves as the clock heartbeat of the system, asserting trigger events to dictate exactly when the ADC should observe. By sampling at a fast enough rate, the machine captures enough snapshots of the signal to represent its behavior across time.

Sampling timing trace showing periodic capture ticks
Sampling timing trace showing periodic capture ticks

4. Quantization: Slicing the Continuous

Freezing time via sampling is only half the battle. At each sampling moment, the voltage level is still a continuous value with infinite decimal possibilities. A computer has a finite number of bits to represent this value, so it must map this infinite voltage to the nearest level on a pre-defined digital staircase. This mapping process is called Quantization.

Quantization discards the infinite sub-millivolt details, rounding the physical voltage to the closest discrete step. The tiny difference between the true analog voltage and the rounded digital level is called Quantization Error.

Continuous signal mapped onto discrete binary quantization levels
Continuous signal mapped onto discrete binary quantization levels

5. Resolution: The Fineness of the Mesh

How close can our digital staircase approximate reality? That depends on the ADC's Resolution. Resolution refers to the number of binary bits the converter uses to represent the signal, which dictates the number of steps on our measurement staircase.

- A 3-bit ADC has only 23 = 8 steps. The staircase is coarse, jagged, and introduces substantial quantization noise. - An 8-bit ADC provides 28 = 256 steps, which is sufficient for basic sensing but still relatively coarse. - A 12-bit ADC provides 212 = 4096 steps, offering a fine mesh that captures small changes with minimal noise. - A 16-bit ADC offers 216 = 65,536 steps, resolving microvolt fluctuations for high-fidelity audio or medical instrumentation.

By increasing resolution, we make the grid mesh finer, allowing the machine to capture a closer approximation of the physical wave.

Comparison of grid density for 3-bit vs 8-bit resolutions
Comparison of grid density for 3-bit vs 8-bit resolutions

6. Reference Voltage: The Calibration Ruler

To assign digital numbers to analog voltages, the ADC needs a ruler. This ruler is the Reference Voltage (VREF). The reference voltage defines the maximum physical voltage the ADC can measure, which corresponds to the maximum digital count.

If we have a 12-bit ADC (0 to 4095) with a VREF of 3.3V: - An input of 0.0V resolves to 0. - An input of 3.3V resolves to 4095. - An input of 1.65V resolves to exactly 2048.

If the reference voltage fluctuates, our measurements fluctuate too. If VREF drops to 3.0V due to poor power supply regulation, an input of 1.5V will resolve to 2048 instead of 1861, causing a measurement error. Precise calibration of VREF is the cornerstone of accurate physical observation.

Reference voltage acting as a calibrated measuring scale
Reference voltage acting as a calibrated measuring scale

7. The Conversion Pipeline: Sample, Hold, Convert, Store

How does the physical conversion happen? Most microcontrollers use a Successive Approximation Register (SAR) ADC. The hardware processes each sample through a four-stage pipeline:

1. Sample: A physical switch closes briefly, connecting the external pin to an internal capacitor. 2. Hold: The switch opens. The capacitor 'holds' the captured charge steady so the voltage doesn't change during conversion. 3. Convert: A comparator compares the held voltage to a series of voltages generated by an internal DAC. Using a binary search (Successive Approximation), it tests the most significant bit first, deciding whether the signal is above or below half of VREF, and repeats for each bit down to the LSB. 4. Store: Once all bits are decided, the binary result is copied to a data register, raising an interrupt or DMA request so the CPU can read it.

SAR ADC hardware blocks: Sample switch, Hold capacitor, Comparator, and SAR register
SAR ADC hardware blocks: Sample switch, Hold capacitor, Comparator, and SAR register

8. Accuracy vs Precision

In embedded sensing, engineers often confuse two critical terms: Accuracy and Precision. They are not the same.

- Accuracy is how close a measurement is to the true physical value. An accurate system has minimal calibration offset. - Precision is how consistent and repeatable the measurements are when the same input is read multiple times. A precise system has low noise.

A system can be highly precise but inaccurate (giving highly repeatable, low-noise readings that are calibrated incorrectly) or highly accurate but imprecise (averaging to the correct value but showing substantial noise on each individual sample). Below is a visual representation of these states:

Imprecise & Inaccurate Precise & Inaccurate Imprecise & Accurate Precise & Accurate

9. Capturing Reality

Let's observe these conversion behaviors. In the interactive panel below, modify signal frequency, resolution, and sampling rate to watch how an analog signal is sliced and rounded into digital numbers.

10. The Cost of Observation

What happens when our observation parameters are configured incorrectly? In the simulator below, adjust the reference voltage, resolution, and sample rate to induce signal clipping, aliasing (undersampling), or high quantization stepping.

11. Real Embedded Applications

ADCs are the sensory organs of embedded silicon. They monitor the health of battery cells in electric vehicles, translate analog temperature sensors (like thermistors or RTDs) into precise degrees, decode phase currents for brushless DC motor control, digitize microphone voice data in smart assistants, and capture cardiac electrical potentials in medical ECG monitors. Without the ADC, a processor is deaf, blind, and isolated from physical reality.

The Sensory Handshake

Timers taught machines when to pay attention. ADCs taught machines how to translate reality into something computation could understand.

Yet observing reality is only half the story. Once a machine has observed its environment and decided on a course of action, it must eventually speak back—driving physical outputs and painting analog actions onto the physical world.

A processor without an ADC is a brain without senses—trapped in a silent chamber of its own logical abstractions.
System Tree Node Coordination

PrajnaEdge

Engineering concepts you don't just read — you experience.
Founded in 2026.

PrajnaEdge is a technology company exploring the space between understanding technology, experimenting with ideas, and turning them into things that can be experienced.

Our Mission

To make technology easier to explore, deeper to understand, and more exciting to experience.

Our Vision

To build a technology ecosystem where curiosity, experimentation and creation continuously lead to one another.

Where it began

Embedded Systems

PrajnaEdge began with Embedded Systems — exploring the foundations that connect hardware, software and intelligent computation.

The first technology universe is built around that foundation. The journey will expand as new ideas, experiments and products emerge.

PrajnaEdge is a technology company created by Devaharsha Meesarapu.

CREATOR PROFILE

Devaharsha Meesarapu

Embedded Systems • Firmware • Edge AI

I am the engineer behind the design, development, and content of PrajnaEdge. I build low-level systems where code directly controls hardware, bridging the gap between register-level silicon behavior and intelligent edge decision loops.

View Resume →

ABOUT ME

I am an Embedded Firmware Engineer focused on developing software for resource-constrained systems. My experience spans bare-metal firmware, device drivers, microcontroller peripherals, and communication protocols, working across the boundary between hardware and software.

My work has involved microcontroller-based systems, real-time behaviour, hardware interfaces, and communication technologies such as CAN, CAN FD, UART, SPI, and I²C. I am particularly interested in understanding systems from the lowest level upward—from registers and peripherals to intelligent edge systems.

ENGINEERING PHILOSOPHY

Engineering is not just about writing code; it is about managing constraints, timings, and physical hardware characteristics. True mastery of complex systems comes from understanding the interactions across different layers of the stack.

This conviction is why I built PrajnaEdge—to bridge the gap between conceptual theory and direct, register-level physical reality.

CONNECT

LinkedIn → GitHub →

Interactive Career Journey

BTech · ECE

Foundations

Where it all began — understanding the physical layer of computation. Circuits, signals, and systems gave me a mental model of how information moves through hardware.

⬡
Connects to Systems
Understanding circuits directly enables writing firmware that talks to peripherals at the register level.
What it is
BTech in Electronics and Communication
Undergraduate foundation covering analog & digital circuits, signal processing, microprocessors, and communication systems.
CircuitsSignal ProcessingMicroprocessorsVLSI
What I did
Core Engineering Fundamentals
Studied semiconductor physics, digital logic design, and embedded microcontrollers. Built prototypes using 8-bit MCUs.
8051Logic DesignPCB Basics
What I learned
The Hardware Mental Model
Every software abstraction sits on physical reality. Understanding silicon teaches you why timing, power, and noise are first-class engineering problems.
Let's Connect
Interested in embedded systems, AI, or building something meaningful? I'd love to hear from you.
Open to collaborations, research, and interesting engineering conversations.
Help Improve PrajnaEdge
Found something to improve? I'd love to hear your thoughts.

Bare Metal

Software that runs directly on hardware without an operating system.

Applications
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Bare Metal
Processor
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Hardware

"Every embedded application begins long before main()."

Operating Systems

An Operating System manages hardware and software resources so complex applications can work efficiently.

Applications
↑
YOU ARE HERE
Operating Systems
Bare Metal
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Processor
↑
Hardware

"When one loop is no longer enough to carry the burden."

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