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.

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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.

PrajnaEdge Navigation Tree
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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Operating Systems

The Invisible Translator

How every Virtual Address finds its way to Physical Memory.

Operating SystemsMemory ManagementVirtual MemoryPhysical MemoryMMUTLBPage Table

1. The Invisible Translator

Software operates entirely inside a world of Virtual Addresses. Physical RAM, however, understands only concrete physical silicon locations.

For any instruction to load, any variable to be read, or any pointer to be dereferenced, the CPU must translate the virtual address into a physical one. This translation happens silently on every single memory cycle.

Because of this constant execution demand, address translation cannot be handled by operating system software alone; querying software loops on every instruction fetch would make the processor crawl.

Instead, the translation is performed by a dedicated hardware component sitting directly on the CPU silicon: the MMU (Memory Management Unit).

Whenever the CPU executes an instruction that references a virtual address, the hardware intercepts the request and routes it through the MMU. The MMU acts as the gateway, converting the virtual target on-the-fly to a physical address before sending it out along the motherboard's memory bus to the RAM chip.

2. The Translation Journey

To perform this translation, the MMU consults two main structures: a fast hardware lookup cache called the TLB (Translation Lookaside Buffer) and a complete mapping directory in memory called the Page Table.

Here is the path every memory request travels from the processor core to physical silicon:

CPU Core Virtual Addr CPU SILICON (MMU) TLB Cache Recent Translations HIT MISS Page Table Walk Consult RAM Directory Physical RAM

3. Why another cache?

Without the TLB cache, virtual memory would cut system performance in half.

Because the main mapping directory (the Page Table) resides in RAM, every variables lookup would require two separate physical memory reads: first, the MMU must read the Page Table from RAM to discover where the physical address is; second, it must read the actual variable data from that address.

Since physical RAM accesses are slow compared to the CPU's cycle speed, doubling the number of memory calls for every instruction fetch would degrade execution speeds.

The TLB acts as a local hardware cache directly inside the MMU, storing the most recently used translations. When the CPU requests an address that has been translated recently, the MMU retrieves the mapping instantly from the TLB, requiring only a single read from RAM to fetch the actual data.

No TLB (Double Latency) 1. Lookup mapping in RAM 2. Fetch actual variable from RAM🛑 2 Memory Bus Access Cycles With TLB Hit (Fast Track) 1. Lookup mapping inside TLB (Instant) 2. Fetch actual variable from RAM🟩 Only 1 Memory Bus Access Cycle

4. Where is the Page Table?

Because the TLB is small, it can only hold a fraction of the translations. The complete list of mappings is stored inside the Page Table.

A common misunderstanding is that the Page Table is a separate hardware unit inside the processor.

It is not. The Page Table is simply a data structure residing in physical RAM, created and managed by the operating system kernel.

Every process has its own isolated Page Table. When the CPU switches tasks, it updates a special register in the MMU pointing to the physical memory location of the active process's Page Table.

If the requested mapping is not in the TLB (a TLB Miss), the MMU hardware automatically pauses the instruction execution, reads the mapping from the Page Table in RAM, updates the TLB, and resumes execution.

Active Process References: 0x1000 MMU Directory Pointer PHYSICAL RAM Process Page Table 0x1000 → Frame 4 0x2000 → Frame 9 (Lives in RAM) Physical Frames Frame 4 (Data)

4.1.1 EdgeCase: One Memory Access

5. A Common Misunderstanding

Many beginners think that Virtual Memory is a physical memory expansion, like adding another RAM chip or swapping files directly to disk to act as memory.

It is not. Virtual Memory is purely an addressing abstraction.

For example, a low-power microcontroller may have only 4 KB of physical RAM, yet the operating system can run processes using a 64 KB Virtual Address Space. This does not mean the system somehow created 60 KB of additional physical memory.

It simply means that the virtual range contains address numbers that can potentially be translated. At any given moment, only a few select virtual addresses are mapped to the actual 4 KB of physical RAM.

If an application attempts to access a virtual address that does not currently map to a physical silicon coordinate, the hardware halts the operation, letting the kernel decide how to resolve the missing link.

Virtual Space (Large) e.g. 64 KB Address Range Page 1 (Mapped) Page 2 (Unmapped) Physical RAM (Small) e.g. 4 KB Silicon Chips Physical Frame 1 Mapping Layer

Most of the time, every process lives inside its own isolated world.

But occasionally, two completely different virtual worlds may quietly point toward the same physical location.

When that happens, the illusion of isolation disappears, and two independent processes can quietly begin exchanging information through the same physical memory. If you'd like to see how that conversation happens, revisit the IPC exploration.

6. Ending

Every process uses its own isolated Virtual Address Space. The MMU hardware dynamically translates virtual coordinates, the TLB speeds up lookup processes, and the Page Table stores the structural configuration database.

But another mystery remains:

How does the Page Table know where every Virtual Address should go?

System Tree Node Operating Systems

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

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

← Return to Systems Tree
Select Domain
Explore application domains branching from the Systems Tree
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← Return to Systems Tree
Select Depth
Examine computation through architectural depth layers
Architecture
Controller
Digital
Programming
Processor
Explore Processors → Explore Controllers →

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