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Andreas Biri edited this page Aug 18, 2021 · 10 revisions

RocketLogger Hardware Initial Operation

When receiving an already assembled RocketLogger device, these step were likely performed for you already and therefore can be skipped.

A newly assembled RocketLogger hardware should be tested and configured before the first measurement. The assembly test section serves for hardware debugging purposes in case of problems during the hardware setup.

The following equipment is required for the initial hardware setup:

  • The RocketLogger cape to set up
  • BeagleBone Green or Black with installed RocketLogger software
  • 5 V, 2 A micro USB power supply
  • Multimeter
  • Tiny screwdriver or knife for adjusting trimmers
  • (For testing only) One or two power supplies with current limiting and measuring capability

Hardware Setup

  1. Attach the RocketLogger cape to a (unpowered) BeagleBone
  2. Power up the RocketLogger by connecting the power supply. The power LED should light up and stay on, the other LEDs should start flashing at irregular intervals after about 5 seconds.
  3. Ground all the voltage inputs and start a RocketLogger measurement in interactive mode or using the web interface. Verify that the measurement values reported are within:
    • < 100 mV for voltage channels,
    • < 1 µA for low current channels,
    • < 1 mA for high current channels.
  4. Measure the offset voltages on test points TP306_1 and TP306_2, and adjust these voltages to 0 V by adjusting R317_1 and R317_2 using a screw driver. The referred components are located on the left under the shield, seen in the Physical Dimensions overview diagram.
  5. Measure the digital input threshold on TP400 and adjust it to 1 V using R401 on the top left of the cape.

    The RC time-constant is quite high, expect some lag when adjusting R401.

  6. The hardware initialization is complete. If not available already, now would be a good time to perform a RocketLogger Calibration.

Please make sure to briefly check the Hardware Errata to learn about known limitations of the hardware.

Assembly Test

For standalone hardware debugging or verification of a RocketLogger cape after assembly, follow the test procedure detailed below:

  1. Connect GND (P9 pins 1, 2 / TP413), all voltages are referenced to GND
  2. Connect 3.3 V (P9 pins 3, 4 / TP415)
    1. Current limit: 20 mA
    2. The idle current draw should be < 10 mA (reference measurement: 0.27 mA)
    3. The 3.3 V rail may be disconnected
  3. Connect 5 V (P9 pins 7, 8 / TP412) using a power supply
    1. Current limit: 1000 mA
    2. The current draw should be close to 0 mA
    3. Keep this rail connected for the remainder of the tests
  4. Connect 5 V or 3.3 V to PowerEnable (P9 pin 13 / TP414)
    1. The current draw should be 5 mA or 3.3 mA respectively (on board 1 kΩ pull-down resistor to GND)
    2. The current draw on the 5 V rail should now be: 135 mA ± 20 mA
    3. Keep the PowerEnable connection for the remainder of the tests
  5. Check all the voltage supply test points:
    1. TP402: +6.8 V ± 0.3 V
    2. TP403: -6.8 V ± 0.3 V
    3. TP408: +6 V ± 0.25 V
    4. TP409: -6 V ± 0.25 V
    5. TP411: +2.5 V ± 0.1 V
    6. TP410: -2.5 V ± 0.1 V
    7. TP407: +5 V ± 0.15 V
    8. TP406: -5 V ± 0.15 V
  6. Check the compensation test points:
    1. TP404: +400 mV ± 50 mV
    2. TP405: -400 mV ± 50 mV
  7. Disable and disconnect all power supplies
  8. Continue with the Hardware Setup section
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