Chainik & Pobeditel
Chainik Chainik
Pobeditel Pobeditel
Pobeditel Pobeditel
Hey Chainik, ever thought about building a tiny wearable that tracks heart rate and automatically tweaks your workout intensity for maximum efficiency? I could set up the data pipeline to turn those readings into real‑time training stats.
Chainik Chainik
Wow, that sounds super cool! I could start with a tiny microcontroller, maybe a BLE chip, and a simple pulse sensor to grab the heart rate. Then use the data to trigger a small motor or LED to signal intensity changes. Battery life will be a challenge – maybe a tiny Li‑Po pack? I’m still figuring out the best way to read the pulse with a low‑power board, but I could sketch a prototype and see if it fits on a wrist band. What do you think about adding a quick visual display or maybe a small buzzer to give feedback? And don’t worry about the code, we’ll just loop through the basics and iterate. Let’s get started!
Pobeditel Pobeditel
That’s a solid plan, Chainik, but let’s nail the numbers first. Pick a BLE MCU that can sleep at 10 µA and wake in 2 ms, otherwise you’ll kill the Li‑Po before the first push. The pulse sensor needs a 10‑bit ADC at 50 Hz – nothing fancy, just keep the conversion time short. If you throw in a tiny OLED, the extra 2 mA will shave a week off the battery, so weigh that against the visual benefit. A buzzer is fine for low‑power alerts, but an OLED gives you real‑time data, which is a game‑changer for iterative tuning. Get a quick sketch, log the current draw for each state, and tweak the duty cycle. I’ll help with the code loops, just keep the logic tight – no fluff, just measurable progress. Let's make this wearable run on a single charge for at least 8 hours of training. Ready?
Chainik Chainik
Got it, I’ll start looking at the nRF52840, it hits 10 µA in deep sleep and wakes fast enough. For the ADC, I can use the MCU’s built‑in 12‑bit ADC but only read 10 bits at 50 Hz – that keeps conversion time short. The OLED idea is tempting; 2 mA isn’t huge, but I’ll test a low‑power e‑ink first to see if it saves even more. I’ll sketch a state diagram: sleep, wake, read sensor, process, display or buzz, back to sleep. Then I’ll measure current in each state, calculate duty cycle, and iterate. I’m a bit nervous about hitting that 8‑hour mark, but I’ll push the limits and keep the code tight. Let’s do it!
Pobeditel Pobeditel
Nice choice with the nRF52840, it’s a solid base for low‑power. Keep the ADC sampling window tight and debounce the heart‑rate signal – jitter slows you down. The e‑ink is a smart move, it draws almost nothing when static, so you’ll get the 8‑hour sweet spot easier. When you measure, compare the sleep current to the wake current, and adjust the wake‑up interval until the average stays under that 300 µA threshold. And remember, if the display isn’t critical for the first prototype, drop it and let the buzzer handle feedback – you’ll save both power and time. Push the limits, iterate fast, and keep the code lean. Let’s hit that endurance target and prove it’s not just talk.