Hardware Reference
In-Depth Information
3.
Measure the voltage between P1-02 (+5 V) and P1-25
(Ground): expect +4.75 to +5.25 V.
4.
Measure the voltage between P1-01 (+3.3 V) and P1-25
(Ground): expect +3.135 to +3.465 V.
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Be very careful with your multimeter probes around the pins of p1.
Be especially careful not to short the +5 V to the +3.3 V pin
, even for a fraction of a second.
Doing so will zap your pi! If you feel nervous or shaky about this, leave it alone. You may end
up doing more harm than good. as a precaution, put a piece of wire insulation (or spaghetti)
over the +3.3 V pin.
Caution
The left side of Figure
2-5
shows the DMM probes testing for +5 V on header strip
P1. Again, be very careful not to touch more than one pin at a time when performing
these measurements.
Be particularly careful not to short between 5 V and 3.3 V
. To avoid a
short-circuit, use a piece of wire insulation, heat shrink tubing, or even a spaghetti noodle
over the other pin.
Figure 2-5.
Measuring voltages
