Hello,
Just trying to get my head around optical pulse sensing with the following sensor:
http://shop.openenergymonitor.com/tsl257-optical-pulse-sensing-kit/
I've read a bunch of pages but still a little confused about connecting the sensor to an emonTx v3.
The shop picture shows the sensor with a 3 core cable and 3.5mm jack, but all pages I've read talk about connecting wires to input pins.
I'm a little confused.
So should I solder the 3 core wire, 3.5mm jack and sensor together, then plug the 3.5mm jack into one of the EmonTx v3 sensor input ports (if yes, which one)?
... or do I forget about the 3.5mm jack, and use the 3-core wire to solder the sensor directly onto the board?
If someone could post a pic of this working, I'd really appreciate it.
Thanks in advance!
Re: connecting TSL257 optical pulse sensor to EmonTx v3
I see your problem. The shop page refers only to the emonTx V2, which has a 3.5 mm jack socket for the pulse input connection. On your emonTx V3, you have a terminal block.
You need to forget the jack plug, and wire the sensor into the terminal block:
GND - GND
VDD - 3.3V
OUT - Dig 3 / IRQ1
The data sheet (download from the shop page) identifies the TSL257 connections, and the terminal block connections are on the underside of the board.
There's a sketch here: https://github.com/openenergymonitor/emonTxFirmware/tree/master/emonTxV3...
but a mistake (not converted from the V2!):
In the comments: port 4 should be IRQ1 / Dig 3
and a little further down:
attachInterrupt(0, onPulse, FALLING);
should be
attachInterrupt(1, onPulse, FALLING);
I haven't got a TSL257 to test.
Re: connecting TSL257 optical pulse sensor to EmonTx v3
Awesome. Thanks!