Hacker News Reader

Comment by winrid | Hacker News Reader

Would an esp32 be the best soc for LoRa? I don't need WiFi or BT, which I know I can turn off to save power. Contemplating trying STM32 instead, don't have experience programming it yet.

View on HN

No. All you would need is a SPI interface or whatever the Lora module speaks. The most basic microcontroller can do that. Any ESP32 is overkill for this.

Right. Sorry I meant development boards. This is low volume, probably will only make a few a year. The nice thing about the esp32 is I can get the board with lora/display built in, with a battery, for $25 each. The stm32 board and module is only a tiny bit less, for example. If I wanted to I could do this with a cheap 8bit microcontroller, I would just have to design a custom board with an oscillator to modulate the IR LEDs etc. I was gonna do that with PWM from the microcontroller to "simplify" things.

Edit: oh the MSP430 is neat! If I cared about battery life (driving 200ma of LEDs anyway...) I'd totally use that.

The XIAO RP2040 looks perfect for what I'm doing, actually, and draws less power.

https://www.seeedstudio.com/LoRa-E5-Wireless-Module-Tape-Ree...

Use something based on the STM32WLE5JC or a discrete SX1262.

If I needed to build a bunch I'd definitely go that route - that's a great deal!

The heltech boards are pretty popular, also have some nice stuff like a screen and a lipo charge controller integrated. They’re really popular with the Meshtastic community.

Yep! Unfortunately the lipo setup is useless, not only would I not trust the lipo in the heat it will be in, I need to drive some other stuff and it will have a much bigger battery pack anyway. Other than that the heltech boards look great, but I'm gonna try something 1/2 the cost and should work fine, and be smaller.

Reply on news.ycombinator.com