You are reading a single comment by @Gordon and its replies. Click here to read the full conversation.
  • Hi, I'll just answer each in turn.

    1) Yes, there is an external oscillator and the RTC is built into the chip. There is no external battery backup, so you need to keep power applied to the chip. You could always add an external RTC if that's an issue, but realistically you'd probably just keep power on the chip all the time anyway since it can enter low power modes very easily.

    2) There was actually another thread about this a few days ago. The simplest method would be to use a LiPo charger, 5v switching power supply, and 2 schottky diodes (so with a low voltage drop), but you can do a lot better if you don't need the 5v rail.

    One issue is really that the ESP8266 really isn't very power efficient - so you're only really going to be able to battery-power the board for a sensible amount of time if you're having WiFi off most of the time... Hence why I chose not to push the price up by adding battery management circuitry.

    3) It uses Serial. When I was designing the board this was brought up, but the flash would only be usable when the ESP8266 was off, which limits its use quite a lot! If you really want you can boot the ESP8266 up into bootloader mode and use that to access the flash memory, so it is possible - but it's a huge faff.

    Think of this board more like a NodeMCU, but smaller, and where the USB interface chip has been replaced by a powerful ARM chip.

    The board was designed trying to take forum member's input into consideration over the course of a few months - during that time nobody mentioned LiPo charging at all as far as I remember... I guess I might end up making another board at some point, but I've invested a lot of time and money in getting the current one into production, I have a bunch in stock, and I can't afford to change it now!


Avatar for Gordon @Gordon started