Windows c example, Bash script example, Windows c example 6.7.5. bash script example – Pololu Simple User Manual
Page 98
printf("Setting Target Speed to %d.\n", newSpeed);
smcSetTargetSpeed(fd, newSpeed);
close(fd);
return 0;
}
6.7.4. Windows C Example
For example C code that shows how to control a Simple Motor Controller using its serial interface in Microsoft
Windows, download
(5k zip). This zip archive contains a Microsoft Visual C++ 2010 Express project, and the provided C code can also be
compiled with MinGW. This example is like the previous example except it does the serial communication Windows-
specific functions like CreateFile and WriteFile.
For this example to work, the Simple Motor Controller’s input mode must be Serial/USB, the serial
mode must be Binary, and the CRC Mode must be set to Disabled. These are the default settings that
the controller is shipped with. The controller should be connected to the computer via USB.
6.7.5. Bash Script Example
The Bash shell script below works on Linux and Mac OS X 10.7 or later. It demonstrates how to control a Simple
Motor Controller over USB. You can run it using the example commands given below. You will need to change the
DEVICE argument to be the name of the Simple Motor Controller’s virtual serial port (see
).
For this script to work, the Simple Motor Controller’s input mode must be Serial/USB, the serial mode
must be Binary, and the CRC Mode must be set to Disabled. These are the default settings that the
controller is shipped with. The controller should be connected to the computer via USB.
#!/bin/bash
# Sets the speed of a Simple Motor Controller via its virtual serial port.
# Usage: smc-set-speed.sh DEVICE SPEED
# Linux example: bash smc-set-speed.sh /dev/ttyACM0 3200
# Mac OS X example: bash smc-set-speed.sh /dev/cu.usbmodemfa121 3200
# Windows example: bash smc-set-speed.sh '\\.\USBSER000' 3200
# Windows example: bash smc-set-speed.sh '\\.\COM6' 3200
# DEVICE is the name of the virtual COM port device.
# SPEED is a number between -3200 and 3200
DEVICE=$1
SPEED=$2
byte() {
printf "\\x$(printf "%x" $1)"
}
{
byte 0x83 # exit safe-start
if [ $SPEED -lt 0 ]; then
byte 0x86 # motor reverse
SPEED=$((-$SPEED))
else
byte 0x85 # motor forward
fi
byte $((SPEED & 0x1F))
byte $((SPEED >> 5 & 0x7F))
} > $DEVICE
This script can also be run on Windows, but since Windows does not have bash installed by default it is easier to use
SmcCmd.
Pololu Simple Motor Controller User's Guide
© 2001–2014 Pololu Corporation
6. Using the Serial Interface
Page 98 of 101