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When driving a Tetrix motor, there's an initial current spike when transitioning from a low output to full output (255 or -255), causing the microcontroller to reset when running on bench power.

Information:
The current sensor read a maximum of 2.06, however my bench power supply briefly triggered an over current warning at 6 amps. The signal LED flashed the startup sequence immediately after this and the previous command was not retained, so the microcontroller definitely reset.

Steps to reproduce:

• Connect to bench supply.
• Send the command r1500.
• Microcontroller resets.
  Issue:
  This probably stems from a brownout in the 5V rail, stemming from either the current protection reducing the voltage or the high current draw reducing the voltage. This suggests that there is a very brief high current spike when starting the motor to full speed.

The motor's internal resistance is 5-6 Ohms, which should draw 2A given V=IR, so that further supports the startup spike theory.

Possible solutions:

• Run it on battery power or a higher current supply. When powering it from a NiMH battery, the microcontroller does not reset.
• Add a capacitor to the 12V rail. This would maybe help keep the rail within the 5V regulator's usable range, though it might have to be a big capacitor.
• Add a capacitor to the 5V rail. This would buffer the 5V rail while the voltage drops, though I don't know what effect this would have on the motor driver.