2018-11-19 23:52:48 -04:00
|
|
|
# CubeBlack Flight Controller
|
|
|
|
|
|
|
|
The Hex CubeBlack flight controller is sold by a range of resellers
|
|
|
|
listed on the
|
|
|
|
[ProfiCNC website](http://www.proficnc.com/content/13-pixhawk2)
|
|
|
|
|
|
|
|
The full schematics of the board are available here:
|
|
|
|
|
|
|
|
https://github.com/ArduPilot/Schematics/tree/master/ProfiCNC/The-Cube
|
|
|
|
|
|
|
|
## Features
|
|
|
|
|
|
|
|
- STM32F427 microcontroller
|
|
|
|
- Two MPU9250 and one LSM303D/L3GD20 IMUs
|
|
|
|
- internal heater for IMU temperature control
|
|
|
|
- internal vibration isolation for first two IMUs
|
|
|
|
- MS5611 SPI barometer
|
|
|
|
- builtin SPI LSM303D magnetometer
|
|
|
|
- microSD card slot
|
|
|
|
- 5 UARTs plus USB
|
|
|
|
- 14 PWM outputs
|
|
|
|
- I2C and CAN ports
|
|
|
|
- Spektrum satellite connector
|
|
|
|
- External Buzzer
|
|
|
|
- builtin RGB LED
|
|
|
|
- external safety Switch
|
|
|
|
- voltage monitoring for servo rail and Vcc
|
|
|
|
- dedicated power input port for external power brick
|
|
|
|
- external USB connectors (micro USB and JST GH)
|
|
|
|
|
|
|
|
## Pinout
|
|
|
|
|
|
|
|
![CubeBlack Board](CubeBlack-pinout.jpg "CubeBlack")
|
|
|
|
|
2018-11-20 00:23:06 -04:00
|
|
|
On each connector the red dot indicates pin 1.
|
2018-11-19 23:52:48 -04:00
|
|
|
|
|
|
|
## UART Mapping
|
|
|
|
|
|
|
|
- SERIAL0 -> USB
|
|
|
|
- SERIAL1 -> UART2 (Telem1)
|
|
|
|
- SERIAL2 -> UART3 (Telem2)
|
|
|
|
- SERIAL3 -> UART4 (GPS)
|
|
|
|
- SERIAL4 -> UART8 (GPS2)
|
|
|
|
- SERIAL5 -> UART7 (spare, CONS)
|
|
|
|
|
|
|
|
The Telem1 and Telem2 ports have RTS/CTS pins, the other UARTs do not
|
|
|
|
have RTS/CTS.
|
|
|
|
|
|
|
|
The CONS port was originally used as a debug console, but is now a
|
|
|
|
general purpose UART (debug output is now on USB).
|
|
|
|
|
|
|
|
## Connectors
|
|
|
|
|
|
|
|
Unless noted otherwise all connectors are JST GH
|
|
|
|
|
|
|
|
### TELEM1, TELEM2 ports
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin </th>
|
|
|
|
<th>Signal </th>
|
|
|
|
<th>Volt </th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>TX (OUT)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>RX (IN)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>CTS</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>5 (blk)</td>
|
|
|
|
<td>RTS</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>6 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
### GPS1 port
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>TX (OUT)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>RX (IN)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>SCL I2C1</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>5 (blk)</td>
|
|
|
|
<td>SDA I2C1</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>6 (blk)</td>
|
|
|
|
<td>Button</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>7 (blk)</td>
|
|
|
|
<td>button LED</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td> (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
### GPS2 port
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>TX (OUT)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>RX (IN)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>SCL I2C2</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>5 (blk)</td>
|
|
|
|
<td>SDA I2C2</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>6 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
### CONS port
|
|
|
|
|
|
|
|
The CONS port is an additional UART connected to SERIAL5. The pinout
|
|
|
|
in the CONS port table below is ordered so that the GND pin is closest
|
|
|
|
to the cube. The TX pin is closest to the servo rail.
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2</td>
|
|
|
|
<td>RX (IN)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3</td>
|
|
|
|
<td>TX (OUT)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
### SBUS Out port
|
|
|
|
|
|
|
|
The SBUSo port is a port attached to the IO processor which can be
|
|
|
|
used to output all servo channels via SBUS. It is enabled by setting
|
|
|
|
the BRD_SBUS_OUT parameter.
|
|
|
|
|
|
|
|
The pinout below for the SBUSo port is labelled so that GND is closest
|
|
|
|
to the cube. The 5V pin on the SBUS output port is connected to the
|
|
|
|
servo rail.
|
|
|
|
|
2018-11-20 00:09:51 -04:00
|
|
|
When SBUS output is disabled (by setting BRD_SBUS_OUT to 0) you can
|
|
|
|
use the port for analog RSSI input from receivers. To enable for RSSI
|
|
|
|
input you need to set:
|
|
|
|
|
|
|
|
- BRD_SBUS_OUT 0
|
|
|
|
- RSSI_TYPE 1
|
|
|
|
- RSSI_PIN 103
|
|
|
|
|
|
|
|
You cannot have both SBUS output and analog RSSI input at the same time.
|
|
|
|
|
2018-11-19 23:52:48 -04:00
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2</td>
|
|
|
|
<td>5v(Vservo)</td>
|
|
|
|
<td>+5.0V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3</td>
|
|
|
|
<td>TX (OUT)</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
### SPKT port
|
|
|
|
|
|
|
|
The SPKT port provides a connector for Spektrum satellite
|
|
|
|
receivers. It is needed to allow for software controlled binding of
|
|
|
|
satellite receivers.
|
|
|
|
|
|
|
|
The pinout of the SPKT port given below is given with the 3.3V power
|
2018-11-20 00:23:06 -04:00
|
|
|
pin closest to the cube (pin 3).
|
2018-11-19 23:52:48 -04:00
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1</td>
|
2018-11-20 00:23:06 -04:00
|
|
|
<td>RX (IN)</td>
|
2018-11-19 23:52:48 -04:00
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3</td>
|
2018-11-20 00:23:06 -04:00
|
|
|
<td>3.3v</td>
|
2018-11-19 23:52:48 -04:00
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
### ADC
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>ADC IN</td>
|
|
|
|
<td></td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
### I2C2
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>SCL</td>
|
|
|
|
<td>+3.3 (pullups)</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>SDA</td>
|
|
|
|
<td>+3.3 (pullups)</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
### CAN1&2
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>CAN_H</td>
|
|
|
|
<td>+12V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>CAN_L</td>
|
|
|
|
<td>+12V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
### POWER1&2
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin</th>
|
|
|
|
<th>Signal</th>
|
|
|
|
<th>Volt</th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>CURRENT</td>
|
|
|
|
<td>up to +3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>VOLTAGE</td>
|
|
|
|
<td>up to +3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<td>5 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<td>6 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
|
|
|
|
### USB
|
|
|
|
|
|
|
|
<table border="1" class="docutils">
|
|
|
|
<tbody>
|
|
|
|
<tr>
|
|
|
|
<th>Pin </th>
|
|
|
|
<th>Signal </th>
|
|
|
|
<th>Volt </th>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>1 (red)</td>
|
|
|
|
<td>VCC</td>
|
|
|
|
<td>+5V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>2 (blk)</td>
|
|
|
|
<td>D_plus</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>3 (blk)</td>
|
|
|
|
<td>D_minus</td>
|
|
|
|
<td>+3.3V</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>4 (blk)</td>
|
|
|
|
<td>GND</td>
|
|
|
|
<td>GND</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>5 (blk)</td>
|
|
|
|
<td>BUZZER</td>
|
|
|
|
<td>battery voltage</td>
|
|
|
|
</tr>
|
|
|
|
<tr>
|
|
|
|
<td>6 (blk)</td>
|
|
|
|
<td>Boot/Error LED</td>
|
|
|
|
<td></td>
|
|
|
|
</tr>
|
|
|
|
</tbody>
|
|
|
|
</table>
|
|
|
|
|
|
|
|
## RC Input
|
|
|
|
|
|
|
|
RC input is configured on the RCIN pin, at one end of the servo rail,
|
|
|
|
marked RCIN in the above diagram. This pin supports all RC
|
|
|
|
protocols. In addition there is a dedicated Spektrum satellite port
|
|
|
|
which supports software power control, allowing for binding of
|
|
|
|
Spektrum satellite receivers.
|
|
|
|
|
|
|
|
## PWM Output
|
|
|
|
|
|
|
|
The CubeBlack supports up to 14 PWM outputs. First first 8 outputs (labelled
|
|
|
|
"MAIN") are controlled by a dedicated STM32F100 IO controller. These 8
|
|
|
|
outputs support all PWM output formats, but not DShot.
|
|
|
|
|
2022-01-21 05:11:37 -04:00
|
|
|
The remaining 6 outputs (labelled AUX1 to AUX6) are the "auxiliary"
|
2018-11-19 23:52:48 -04:00
|
|
|
outputs. These are directly attached to the STM32F427 and support all
|
|
|
|
PWM protocols as well as DShot.
|
|
|
|
|
|
|
|
All 14 PWM outputs have GND on the top row, 5V on the middle row and
|
|
|
|
signal on the bottom row.
|
|
|
|
|
|
|
|
The 8 main PWM outputs are in 3 groups:
|
|
|
|
|
|
|
|
- PWM 1 and 2 in group1
|
|
|
|
- PWM 3 and 4 in group2
|
|
|
|
- PWM 5, 6, 7 and 8 in group3
|
|
|
|
|
2022-01-21 05:11:37 -04:00
|
|
|
The 6 auxiliary PWM outputs are in 2 groups:
|
2018-11-19 23:52:48 -04:00
|
|
|
|
|
|
|
- PWM 1, 2, 3 and 4 in group1
|
|
|
|
- PWM 5 and 6 in group2
|
|
|
|
|
|
|
|
Channels within the same group need to use the same output rate. If
|
|
|
|
any channel in a group uses DShot then all channels in the group need
|
|
|
|
to use DShot.
|
|
|
|
|
|
|
|
## Battery Monitoring
|
|
|
|
|
|
|
|
The board has two dedicated power monitor ports on 6 pin
|
|
|
|
connectors. The correct battery setting parameters are dependent on
|
|
|
|
the type of power brick which is connected.
|
|
|
|
|
|
|
|
## Compass
|
|
|
|
|
|
|
|
The CubeBlack has two builtin compasses. One is a HMC5843 and the other
|
|
|
|
is a part of the MPU9250 IMU. Due to potential interference the board
|
|
|
|
is usually used with an external I2C compass as part of a GPS/Compass
|
|
|
|
combination.
|
|
|
|
|
|
|
|
## GPIOs
|
|
|
|
|
|
|
|
The 6 PWM ports can be used as GPIOs (relays, buttons, RPM etc). To
|
|
|
|
use them you need to limit the number of these pins that is used for
|
|
|
|
PWM by setting the BRD_PWM_COUNT to a number less than 6. For example
|
|
|
|
if you set BRD_PWM_COUNT to 4 then PWM5 and PWM6 will be available for
|
|
|
|
use as GPIOs.
|
|
|
|
|
|
|
|
The numbering of the GPIOs for PIN variables in ArduPilot is:
|
|
|
|
|
|
|
|
- PWM1 50
|
|
|
|
- PWM2 51
|
|
|
|
- PWM3 52
|
|
|
|
- PWM4 53
|
|
|
|
- PWM5 54
|
|
|
|
- PWM6 55
|
|
|
|
|
|
|
|
## Analog inputs
|
|
|
|
|
|
|
|
The CubeBlack has 7 analog inputs
|
|
|
|
|
|
|
|
- ADC Pin2 -> Battery Voltage
|
|
|
|
- ADC Pin3 -> Battery Current Sensor
|
|
|
|
- ADC Pin4 -> Vdd 5V supply sense
|
|
|
|
- ADC Pin13 -> ADC 3.3V Port pin1
|
|
|
|
- ADC Pin14 -> ADC 3.3V Port pin2
|
|
|
|
- ADC Pin15 -> ADC 6.6V port
|
|
|
|
- ADC Pin103 -> RSSI voltage monitoring
|
|
|
|
|
2018-11-20 00:09:51 -04:00
|
|
|
## IMU Heater
|
|
|
|
|
|
|
|
The IMU heater in the CubeBlack can be controlled with the
|
2021-10-20 07:22:09 -03:00
|
|
|
BRD_HEAT_TARG parameter, which is in degrees C.
|
2018-11-20 00:09:51 -04:00
|
|
|
|
2018-11-19 23:52:48 -04:00
|
|
|
## Loading Firmware
|
|
|
|
|
|
|
|
The board comes pre-installed with an ArduPilot compatible bootloader,
|
|
|
|
allowing the loading of *.apj firmware files with any ArduPilot
|
|
|
|
compatible ground station.
|
|
|
|
|
|
|
|
## Acknowledgements
|
|
|
|
|
|
|
|
Thanks to [ProfiCNC](http://proficnc.com) for images
|