Tag Archives: release

moteus-n1 beta release

Implied by my previous writeup on pin selection for external connectors, we’ve got a new variant of the moteus controller to announce today in beta form, the moteus-n1!

This variant is intended to be more feature-full, higher performance (and higher cost). Here are some bullet points of the biggest differentiators with r4.11:

moteus n1moteus r4.11
Price$159 USD @ qty 1$104 USD @ qty 1
SizeAs small as 46mmx46mmx8mm with optional back connectors omitted.

58% of the volume, 87% of the top down footprint size of r4.11
External PeripheralsEach of the auxiliary connectors supports SPI, UART, ADC, SW & HW Quadrature, Hall sensors, and I2C.

5V and 3.3V is provided on each connector to power peripherals (100mA for each voltage available combined between both connectors).

I2C pullups are configurable on each connector.

All 4 pins on AUX2 are 5VT, the two non-SPI pins on AUX1 are 5VT.
ENC (AUX1) supports SPI, Hall and ADC.

ABS (AUX2) supports UART and I2C and are both 5VT.
RS422Built in RS422 transceiver for communicating with RS422 / BiSS-C encoders (BiSS-C / SSI not yet supported in software).None
Voltage8-54V, 48V nominal8-44V
Peak Output100A output phase current, 1200W100A output phase current, 500W
Continuous Output10A output phase current ambient, 20A w/ thermal management10A output phase current ambient, 20A w/ thermal management
CAN fault tolerance58V bus fault tolerance12V bus fault tolerance
Power ConnectorsSolder pads for DC bus input, one always present XT30, one optional XT302x XT30

The short form is that the n1 does not really expand the set of motors that can be usefully driven, but does enable operation in 48V systems, is more compact and electrically robust and provides significantly improved external peripheral support.

Don’t worry, the existing r4.11 controllers aren’t going anywhere and are still being produced. The moteus-n1 series just complements them by enabling new applications.


Both the moteus n1 and r4.11 share the same open source firmware, although the n1 requires a newer release to operate. Command, control, and monitoring work identically on both, including tview, the python library, and all CAN formats. The only exception is that the n1 has more external pin configurations possible as shown in the reference documentation’s pin capability table.


The mechanical form factor of the n1 is different from r4.11, and thus the existing devkit bracket and heat spreader can not be used. New variants exist for both of those that are compatible with the n1.

The XT30 and JST PH3 board connectors are now available for sale separately in order to convert n1’s to have daisy chain connectors.

Finally, all the external peripheral connectors use JST-GH connectors, so we now have headers and pre-crimped wires available for the JST GH6 (used for the RS422), JST GH7 (used for AUX2) and JST GH8 (used for AUX1).

Beta availability

Starting today we’re making some moteus-n1 units available in a paid beta program, with errata documented here. Up to 2 controllers in either devkit or bare board form (both bare board and devkits variants count towards the total) can be ordered per customer via the links above. There is no technological limit if you try to exceed that, you will just have your order cancelled with a note to try again with fewer.

Good luck!

moteus firmware 2023-02–01

Partly to celebrate moteus controllers being back in stock and partly because a lot of important work has backed up, we’ve just released a new firmware version for moteus (2023-02-01) that has a little bit of something for everyone. Future posts will examine some of these features in more detail, but for now you just get the bullet list:

  • Support sending and receiving arbitrary data from a UART configured on either of the auxiliary ports
  • Permit I2C encoders to operate at up to 1kHz
  • Report control position, velocity, and torque as well as the errors in tracking them over the register protocol as 0x038-0x03d
  • Provide support for synchronizing the clock of a moteus controller with a host application
  • Report hall effect errors
  • Expose the drv8353 error flags as register 0x140 and 0x141
  • Fix register 0x006 (ABS port position) to be reported in revolutions

moteus firmware release 2022-07-11

It has been on github for a few days now, but I’m excited to announce the newest moteus firmware release, 2022-07-11. This release includes some big features, and some quality of life improvements all around.

  • Flexible I/O subsystem: This release includes the new flexible I/O subsystem. This adds support for many new encoder types and lets you connect them up in a wide variety of ways.
  • Cogging torque compensation: Preliminary support for cogging torque compensation is present in this release. It works pretty well on a number of motor types already, future articles will describe it in more detail.
  • Encoder eccentricity compensation: This feature lets you linearize the output position and velocity in the face of non-linear encoder readings. A write-up for it is also forthcoming in the not-too-distant-future.
  • Transparent no-BRS CAN-FD communication: If your CAN-FD network is only capable of operating at 1Mbps, and you send queries frames with BRS turned off, moteus will now respond in kind. This eliminates most needs to change the CAN bus frequency due to marginal electrical properties.

This is an exciting time for moteus, and the new features will keep coming!

New moteus firmware release, 0.1-20200822-1

I’ve posted a new release of the firmware for the moteus brushless controller to github!

This release has a number of minor improvements in the host tools (for which there continue to be no distributed binaries, you get to build from source). The biggest improvement in the firmware is the improved low-torque operation as documented here and here. If you have any questions or want help upgrading, hop into discord at #moteus and ask!