Hello,

        I've got a 16f870 that I'm using to turn a relay (Tyco V23105 150 mW
Nominal Coil Power, 960 ohm, 12 volt Nominal Coil Voltage) on/off.  This
relay is controlling a very small DC motor (~0.5amps).  About 10% of the
time when this relay turns on/off, it resets the PIC.  I've verified this
is what's happening.  Seems to work fine when the motor isn't connected to
the relay.  Only resets when the motor is connected.
        I'm using PORTA.0 through a resistor to turn on a 2N4401 transistor that
then powers the relay coil.  I have a 1N4004 diode across the relay
coil.  I have two 0.1uf caps on the +5v to the PIC.
        The +5v for the PIC is from a powered protoboard.  The +12v for the
transistor and relay are from a +12v battery.  The grounds of these two
power supplies are tied together.
        Can anyone help me figure out what's going on and fix this?

Thanks,

Gary

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