Tinderbox Power

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This page describes the instrumentation of the Tinderbox laptops to measure power, and the scripts used to measure and interpret this information.

Instrumentation

Configuration File Format

The key to this is the comma separated values (CSV) file describing the instrumentation. This scriptlet takes a file of format:

channel,name,resistance,rail_voltage,rail

where

  • channel is the voltmeter channel (absolute, e.g. 2010, 3020, etc.)
  • name is the name associated with this channel
  • resistance is the resistance of the current sense resistor
  • rail_voltage is the voltage at the high side of the current sense res.
  • rail indicates that a voltage varies, and is measured by another channel. If rail is:
    • 0 - indicates rail_voltage is static and should be used
    • positive number - indicates which rail should be used
    • negative number - indicates that this is a rail voltage

See the example configuration files for the existing [1] and [2] setups.

Measurement