What would be a helpful is a debug module that could monitor current and voltage for a Gadgeteer module. I’m testing a module now and I’d love to know how much power it is eating as I suspect its eating more then it should. Gadgeteer based modules/tools to test Gadgeteer based projects, what could be better.
1 Like
Love the idea
Doable. 
You just want to measure the current on the 5V and 3.3V?
This must be a gadgeteer module that measures a gadgeteer module, right?
It should measure current on both sides individually.
Yes a module that measures other modules!
@ Gus - does that mean it’s self aware? :whistle:
Measure current on 5V and measure current on 3V3? Or am I missing something?
I’m busy with a lipo module, but this will be quick and some needed distraction. 
The module will have three sockets, one that outputs the measured current, an in and an out for the module pass though.
Required maximum current and required resolution?
Max current would be whatever the biggest gadgeteer mainboard can handle to date times 2 plus fudge, so 2-3A maybe? Resolution - lower is better within reason (cost). Possible to get plus or minus 10mA on the cheap? Anything lower seems overkill. Put me down for one.
You’re talking about a Rewire module, except backwards? All the non-power pins routed straight through, with the 3V3 and 5V pins broken out (and not routed through) so they could be measured with an ammeter?
I was assuming the module did the measurement and output it somehow… my aim would be to measure current over time and record it. No external measurement involving a human and other meters required…
So, there would need to be three Gadgeteer sockets on it, then… an “in from mainboard”, an “out to module”, and a “data return to mainboard”.
I see this module having 3 sockets. 2 are connected just like extender module but with circuitry in teh way to measure current and voltage and then there is a third socket that connect to maybe I2C to read the measured values.
Could be done. A couple of shunt resistors, an ADC, nothing very complex.
Even more interesting, connect it between red module and mainboard and now you are measuring the whole system! Very sweet!
Then you will need both positive and negative current measurement. Makes it more expensive… 
The simple way is to use two 0.05 ohm resistors, two current amplifiers and connect their outputs to an “A” socket.
Why negative? no no, you do not need that Think about it…you just nee dot connect it backwards where the mainboard is the module!
How do you explain that to the user?
few pictures will do I think
Gus, how does one lable an “any” socket?
Can a module driver be written so this module acts in the designer as it will in real life? IE, one input socket wuth “any” requirement, and one output socket that another module can connect to?
What do I put on the PCB next to the sockets?
You can’t. I had this issue with the Rewire module. The Gadgeteer spec does not allow for this sort of thing. I put blank boxes where a user could write their own letter, but in this case, that doesn’t even make sense, because it could change.
The closest thing in the spec would be * which means “downstream module in a DaisyLink chain”
“ABCDEFGHIKOPRSTUXYZ*”
Any other questions? 