Welcome to ODRI Motor Board Configuration’s documentation!

The user_config_f28069m_drv8305 repository contains the firmware configuration files for the ODRI project. They are based on the config files included in the MotorWare examples and can be used for those. Likewise they are used by our firmware (both CAN and SPI versions).

Note

The structure of these config files is not ideal. Configuration is duplicated for the single-motor and dual-motor applications and also some global, motor-indepented values (like CPU frequency) are duplicated in the config files for the second motor but those duplicates are not used anywhere.

This is because the files are based on the configuration files of the MotorWare example projects and probably were not meant to be used like this in production. However, we keep this structure to preserve compatibility with those example projects.

About the Different Files

There are different files for single motor and dual motor projects. For each case there are again separate files for the motors connected to J1 and J5. Lots of the content of these files is the same so there is quite some copy&past mess.

Single Motor Applications

Filename	Purpose
user.h	Main configuration file. Configures the microcontroller and which of the motors is used (J1 or J5).
user_j1.h	Configuration specific for the motor and inverter board on J1.
user_j5.h	Configuration specific for the motor and inverter board on J5.

Note that user_j1.h and user_j5.h have exactly the same structure.

Dual Motor Applications

Filename	Purpose
user1.h	Corresponds to user.h for single motor applications and includes config for J1
user2.h	Same as user1.h but includes config for J5.1
user_mtr_on_j1.h	Same as user_j1.h.
user_mtr_on_j5.h	Same as user_j5.h but all defines are suffixed with “_2”.

¹ Note that user2.h also duplicates all the global settings of user1.h (e.g. CPU frequency), which does not really make sense. Those settings are most likely not used anywhere, as the ones from user1.h are used.

Note

Note that configuration for J1 is duplicated between user_j1.h and user_mtr_on_j1.h, so make sure to apply relevant changes to both files. The same holds for user_j5.h and user_on_mtr_j5.h (where the latter has suffix “_2” in all defines).

Select Motor in Single-Motor-Application

When running a single motor application (i.e. one that uses user.h instead of user1.h, user2.h, it has to be defined in the configuration file which of the two slots (J1 or J5) shall be used. This is done in user.h. At the top of the file there is a line

#define J1  // or J5

Set this to J1 or J5 to use the corresponding motor.

Configure System Frequencies

As explained in Program Structure & Frequencies, different parts of the program run at different frequencies. This is accomplished by defining a base frequency and a set of “decimation factors”. This is done in the *_j1/5.h configuration files, so different frequencies can be set for the two motors.

The base frequency is the PWM, which is defined by USER_PWM_FREQ_kHz in the section “CLOCKS & TIMERS”. For a single motor, this can be set to something like 45. For dual motor applications set it to a lower value as there has to be enough CPU time left for the second motor. It may also be good to set slightly different values for the two motors so that the controllers are not always triggered at the same time (the example projects use 20 and 18, which seems to work well).

The decimation factors are defined in the section “DECIMATION” as follows:

#define USER_NUM_X_TICKS_PER_Y_TICK n

This means that every n-th time X is executed, Y will be run. If X runs with frequency \(f_X\) the resulting frequency for Y will be

\[f_Y = \frac{f_X}{\text{USER_NUM_X_TICKS_PER_Y_TICK}}\]

Example

If USER_PWM_FREQ_kHz = 20, USER_PWM_TICKS_PER_ISR_TICK = 2, and USER_ISR_TICKS_PER_SPEED_TICK = 10, the ISR is executed every second PWM cycle and every 10-th time the ISR is run, it will run the speed controller. This means f_ISR = 10kHz and f_controller = 1kHz.

Below is a complete list of all decimation factors that are defined:

Name	Purpose
USER_NUM_ISR_TICKS_PER_CTRL_TICK	Defines the frequency of the control loop. ⚠️  This is not implemented correctly. Always set it to 1!
USER_NUM_CTRL_TICKS_PER_CURRENT_TICK	Defines the frequency of the low-level current controller. ℹ️  This is actually the not used! The current controller runs at ISR frequency.
USER_NUM_CTRL_TICKS_PER_EST_TICK	Defines the frequency of the FAST estimator. ℹ️  This is not used in our code, as we do not use FAST.
USER_NUM_CTRL_TICKS_PER_POSCONV_TICK	Defines the frequency of the SpinTAC PositionConverter module (responsible for providing motor position and speed). ⚠️  Must be at least three times the frequency of highest expected electrical velocity, otherwise velocity will suffer from an overflow!
USER_NUM_CTRL_TICKS_PER_SPEED_TICK	Defines the frequency of the high level controller (which, depending on the firmware that is used, does not necessarily have to be a speed controller).
USER_NUM_CTRL_TICKS_PER_TRAJ_TICK	This is not used by our code.

For the dual_motor_torque_ctrl project (which is the one that is used on the board when it is controlled via CAN), only the bold factors should be modified.

Configure Motor Parameters

Adding new motors to the configuration is handled in Motor Paramter Identification.

Further Reading

Checkout the Texas Instruments’ InstaSPIN-FOC/-MOTION User’s Guide for more information on the various parameters and their effects.