hm-10

Hi All,

I have (a probably stupid) question about hooking up a HM-10 to the espruino. From the BLE example, it states that "In order to use pin 23, connect this pin via a switch to ground (defaul position of the switch is open). Also connect this pin via a resistor of 1k to 3.3V."

My question is: why can't I just connect pin 23 to any GPIO pin of the espruino? The idea is to have 3.3V go into the HM-10 if the pin is off and to have it grounded when the pin is on right? Wouldn't you have that with the GPIO off (ground) and the GPIO on (v-in)?

I'm not too familiar with hardware so if anyone could please clarify this for me I'd be very grateful. Also, I assume a 470R resistor is a 470 Ohm resistor?

EDIT: why does it have to specifically be a 470? Would a 1K work?

Regards,

Alex

470R is definitely 470 Ohm, and yes, it could probably be anything from 500-20000 Ohms (or more!).

You could connect directly to Espruino as you say (skipping the resistor + switch) - I don't see any reason why not, as the pin seems only to be an input to the HM-10.

Hi Gordon,
Thank you for your answer :) I thought it strange that the picture on that page didn't look like it followed the description.