Firefox OS/Performance/Power/Sample Delay Calibration of COTS Ammeter: Difference between revisions
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==Setup and Methodology== | ==Setup and Methodology== | ||
I used a [https://goodfet.sourceforce.net Goodfet] digital I/O peripheral to toggle on a digital I/O pin and then measure the delay until the ammeter measures current. | I used a [https://goodfet.sourceforce.net Goodfet] digital I/O peripheral to toggle on a digital I/O pin and then measure the delay until the ammeter measures current. I wrote some custom firmware for the Goodfet and a python client that interfaced with the yoctopuce ammeter to measure the delay between the goodfet pin going high and the ammeter seeing a measurable increase in current. | ||
The code work is in the [https://github.com/dhuseby/goodfet/tree/fxos/ fxos branch] of my fork of the [https://github.com/dhuseby/goodfet/ goodfet repo]. | |||
==Data and Results== | ==Data and Results== | ||
Revision as of 23:04, 17 September 2013
Calibrating for Initial Sample Dealy of COTS Ammeter
The Yoctopuce Ammeter we're using for the initial baselining of power consumption of Firefox OS has a small delay before we receive the first sample over the USB connection. This page documents the method used to measure the delay so that we can use it to time-corelate the power usage data with other profiling data for analysis.
Setup and Methodology
I used a Goodfet digital I/O peripheral to toggle on a digital I/O pin and then measure the delay until the ammeter measures current. I wrote some custom firmware for the Goodfet and a python client that interfaced with the yoctopuce ammeter to measure the delay between the goodfet pin going high and the ammeter seeing a measurable increase in current.
The code work is in the fxos branch of my fork of the goodfet repo.