beagleboard/beaglebone-blue

Identification of motor driver pins

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I have not found a document that tells us which pin on the motor driver schematic corresponds to pins 1 or 0 of each motor driver. Where can we find this?

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For example. Is motor 1 pin 1 located on the lower or upper pin in this photo?

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You said "pins 1 or 0", but the connectors label the pins 1 and 2. It is common for hardware to begin indexes at 1 instead of 0.

The hardware design convention is pin 1 gets the square solder pad. You can find the solder pad from the bottom of the board or looking at the board layout.

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The silkscreen attempts to communicate the clockwise numbering of the motor connectors, starting at the lower-right in your picture.

So, motor 1 pin 1 is the lower-right connector on the upper-most pin within that connector, whereas motor 1 pin 2 is the lower-right connector on the lower-most pin within that connector.

There is a nice TB6612FNG motor driver truth-table on Sparkfun's website. I've mapped the pins to the gpio/pwm numbers as defined in the librobotcontrol motor driver and schematic processor ball numbers below:

Mx In1 In2 PWM Out1 Out2 SW correction
M1 GPIO2.0 T13 GPIO0.31 U17 EHRPWM1A U14 2 1 -1
M2 GPIO1.16 R13 GPIO0.10 U17 EHRPWM1B T14 1 2 1
M3 GPIO2.9 R4 GPIO2.8 R3 EHRPWM2A U10 1 2 1
M4 GPIO2.6 R1 GPIO2.7 R2 EHRPWM2B T10 2 1 -1

Note that the software accounts for when Out1 is connected to pin 2 by performing a correction.

This helps very much! Will add this to our robot slides. Thank you.