Library for TMC2209 driver - AVR

This library is used to control one or more TMC2209 modules via UART using an AVR microcontroller. Apart from reading and writing the TMC2209 registers, this library can also be used to drive a stepper motor by using the stepperCon library in the background. The stepperCon library provides non blocking functions by using an interrupt, to drive multiple stepper motors with custom acceleration and speed, to keep track of motor positions, 3-axis motor coordination, as well as other useful functions. UART library is also provided that can use up to 2 USART peripherals at the same time: one for interfacing with the driver IC and one for debugging (assuming the microcontroller has two USART peripherals). 

The serial communication has some extra features for checkup such as:

• reads the interface transmission counter (IFCNT) register after every write to ensure the IC received the correct data.
• compares CRCs.
• checks if correct number of bytes has been received.
• if an error occurs it retries 2 times then sets a communication error flag that the user can check after each function is executed and take the appropriate action if an error occurs. 

The principle of operation is read-modify-write so there is no need to keep all driver IC registers in memory. The library only uses an 8 bytes union structure called replyDatagram where received and data to send is stored temporary.

If you wish to learn on how to wire the TMC2209 driver, you can find a tutorial here.

Contents

• Library Structure
• Default Settings
• Usage
• Documentation
• Create a structure object for each driver
• Initialization
• Read IC version
• Read Global Status Flags (GSTAT)
• GSTAT check if module was Reset
• GSTAT check if Driver Error
• GSTAT check if Charge Pump is Under Voltage
• Status check for UART error
• Read register PWM_SCALE_SUM
• Read register PWM_SCALE_AUTO
• Read register PWM_OFS_AUTO
• Read register PWM_GRAD_AUTO
• Read register SG_RESULT (StallGuard)
• Read register TSTEP
• Read register DRV_STATUS (Driver Status Flags)
• DRV_STATUS check Standstill
• DRV_STATUS check Chopper type
• DRV_STATUS check CS_ACTUAL
• DRV_STATUS check Temperature flags
• DRV_STATUS check Open Load flags
• DRV_STATUS check Low Side Short flags
• DRV_STATUS check Short to Ground flags
• DRV_STATUS check Over-temperature flag
• DRV_STATUS check Over-temperature Pre-warning flag
• Set micro-step resolution
• Set speed
• Set acceleration and deceleration
• Set direction
• Set chopper
• Set SpreadCycle threshold
• Set register IHOLD_IRUN
• Set register TPOWERDOWN
• Set register SGTHRS (StallGuard)
• Set register TCOOLTHRS (CoolStep threshold)
• Set register COOLCONF (CoolStep)
• Set Standstill mode
• Enable/disable driver by software
• Move to absolute position
• Move to relative position
• Start TMC2209 internal step generator
• Stop TMC2209 internal step generator
• StealthChop Automatic Tuning (AT)
• Download

TMC2209 stepper driver module tutorial

My first stepper driver module was A4988 and recently I have decided to give TMC2209 a try hearing how silent and energy efficient it is. Driving the A4988 is simple - just set direction, pulse the step pin and the motor moves. You can do the same thing with TMC2209 but this thing can do much more. It has UART interface, registers, algorithms and an 83 pages datasheet. I might be slow but I had to read the datasheet 3 times to wrap my head around on what things can this thing do. In my opinion it is a very good stepper driver so I made a library for it and also this tutorial to better help in using the library. Although the IC presented in this tutorial is TMC2209, most information can still be applied to other TMC ICs.

Contents

• TMC2209 description
• Modes of operation
• TMC2209 module pinout
• Attaching the TMC2209 to a microcontroller UART
• Setting the analog motor current
• Setting the digital motor current
• Automatic Standstill Power Down
• StealthChop2 and SpreadCycle Driver
• StealthChop
• StealthChop Automatic Tuning
• Freewheeling and Passive Braking
• SpreadCycle
• Combine StealthChop and SpreadCycle
• StallGuard4 Load Measurement
• StallGuard4 vs. StallGuard2
• Tuning StallGuard4
• StallGuard4 Update Rate
• Detecting a Motor Stall
• Limits of StallGuard4 Operation
• CoolStep Operation
• Setting up CoolStep
• Tuning CoolStep
• Response Time
• Driver Diagnostic Flags
• Temperature Measurement
• Short Protection
• Open Load Diagnostics
• Diagnostic Output
• Internal Step Pulse Generator
• External Reset
• Links

 

TMC2209 description

The TMC2209 is an ultra-silent motor driver IC for two phase stepper motors, developed by trinamic. TMC2209 pinning is compatible to other drivers as well as to the TMC2208. 

Multiple versions of modules can be found that are using this IC, however the stand-alone chip can be used for a DIY module that could provide some cost savings.

Features:

• 2-phase stepper motors up to 2.8A coil current (peak), 2A RMS
• STEP/DIR Interface with 8, 16, 32 or 64 microstep pin setting
• Smooth Running 256 microsteps by MicroPlyer™ interpolation
• StealthChop2™ silent motor operation
• SpreadCycle™ highly dynamic motor control chopper
• StallGuard4™ load and stall detection for StealthChop
• CoolStep™ current control for energy savings up to 75%
• Low RDSon, Low Heat-Up LS 170mΩ & HS 170mΩ (typ. at 25°C)
• Voltage Range 4.75… 29V DC
• Internal Sense Resistor option (no sense resistors required)
• Passive Braking, Freewheeling, and automatic power down
• Single Wire UART & OTP for advanced configuration options
• Integrated Pulse Generator for standalone motion