TTL Debug Tools¶

This package is a debugging package to setup and access directly to all hardware components on the TTL bus. It provides main functions like ping, scan device and read/write/syncRead/syncWrite operations on devices.

There are two ways to use this package: directly with the compiled binary, or via TTL Driver services called in dedicated scripts.

Ttl debug tool binary¶

The compiled binary (located in install/lib/ttl_debug_tools/ttl_debug_tools) directly accesses the TTL bus using Dynamixel SDK third party library. Thus, it cannot be used if the Niryo ROS Stack is already running and you should first stop the robot stack (sudo service niryo_robot_ros stop)

This tool can be launched via:

rosrun ttl_debug_tools ttl_debug_tools

or

roslaunch ttl_debug_tools ttl_debug_tools

Parameters - Ttl debug tools¶

–help / -h: Prints help message

–baudrate / -b [Baudrate]: Baudrates (1000000 by default)

–port / -p [Port]: Sets port

–id / -i [ID]: Devices ID (-1 by default)

–ids [IDs]: Lists of devices IDs

–scan: Scans all devices on the bus

–ping: Pings specific ID

–get-register [Addr]: Gets a value from a register, parameters is: register address

–get-registers [Addr]: Gets list of values from multiple devices at a register address, parameters is: register address

–get-size [Size]: Size of data to be read with get-register or get-registers, parameters is: size of data in bytes

–set-register [Addr] [Value] [Size]: Sets a value to a register, parameters are in the order: register address / value / size (in bytes) of the data

–set-registers [Addr] [Values] [Size]: Sets values to a register on multiple devices, parameters are in the order: register address / list of values / size (in bytes) of the data

–calibrate: Calibrates all steppers on the bus. It is used in Ned2 only

Scripts¶

In order to use Ttl debug tools to debug an already running ROS stack, it was necessary to develop another tool. To do so, two python scripts have been developped. They ensure access to the data on the TTL bus via two services implemented in the package TTL Driver:

read_custom_dxl_value.py : uses service ReadCustomValue to read values from the TTL bus
send_custom_dxl_value : uses service SendCustomValue to write values to the TTL bus

Niryo robot - Send DXL custom value¶

It uses a ttl_driver service to send data to a register of a device on the TTL bus when the ROS stack is running. This script can be launched via:

rosrun ttl_debug_tools send_custom_dxl_value.py

Parameters - Send custom value¶

–id [ID]: Device ID

–address [Addr]: Registers address to modify

–value [Value]: Value to store at the register address given

–size [Size]: Size in bytes of the data to write

Niryo robot - Read DXL custom value¶

It uses a service to read data from a register a device on the TTL bus when the ROS stack is running. This script can be launched via:

rosrun ttl_debug_tools read_custom_dxl_value.py

Parameters - Read custom value¶

–id [ID]: Device ID

–address [Addr]: Register address to modify

–size [Size]: Size in bytes of the data to read