Dec 2025 – May 2026
Trainee Embedded System Engineer
Smart Computing Pvt Ltd
Work Contributions
- Developed custom firmware on STM32 microcontrollers for the INVEX metering and control project, covering MQTT, Ethernet, and GSM communication paths as well as the LCD interface and interactive display layouts.
- Owned PCB-level debugging and bring-up on INVEX boards, working across power, reset, high-speed signalling, and peripheral interfaces to move boards from first-power to functional state.
- Brought up a 26-pin monochrome LCD from scratch: identified the correct controller documentation, resolved a wiring / driver integration issue, and validated the display end-to-end with real application screens.
- Wrote a reusable, universal monochrome LCD driver on top of U8g2 so the same interface layer could be used across future STM32-based products.
- Performed hands-on power measurements on the LCD subsystem and translated the results into a concrete firmware-level optimisation decision.
Key Achievements
Resolved an STM32 + DP83848 Ethernet bring-up failure by tracing the fault to a missing PHY reference-clock connection (DP83848 OSIN → STM32 PA1 REF_CLK); once corrected, the RMII link came up on first attempt and Ethernet operation was restored.
Delivered a working 26-pin monochrome LCD interface on STM32 by identifying that an incorrect 28-pin datasheet had been referenced, sourcing the correct controller docs, and specifying the missing ceramic capacitors required by the LCD charge-pump / voltage circuit.
Fixed a display initialisation bug by correcting the U8g2 byte callback to properly handle the A0 / command-mode line, after which the LCD came fully alive on the breadboard prototype.
Validated the LCD subsystem against the real application UI — volume, temperature and pressure graphs, contrast control, and backlight operation — confirming driver readiness for product use.
Characterised LCD backlight current draw at 0.160 A (ON) vs 0.002 A (OFF), and drove the engineering decision to add automatic backlight timeout and PWM dimming to extend battery life on the target device.
Built out the INVEX firmware communication stack on STM32 across three transports — MQTT, Ethernet, and GSM — enabling the board to operate as a networked metering / control node.