= Stepper Configuration This section assumes you have done a standard install from the Live CD. After installation it is recommended that you connect the computer to the Internet and wait for the update manager to pop up and get the latest updates for EMC and Ubuntu before continuing. For more complex installations see the Integrator Manual. == Latency Test The Latency Test determines how late your computer processor is in responding to a request. Some hardware can interrupt the processing which could cause missed steps when running a CNC machine. This is the first thing you need to do. Follow the instructions in section (<>) to run the latency test. == Sherline [[sec:Sherline]](((Sherline))) If you have a Sherline several predefined configurations are provided. This is on the main menu CNC/EMC then pick the Sherline configuration that matches yours and save a copy. == Xylotex [[sec:Xylotex]](((Xylotex))) If you have a Xylotex you can skip the following sections and go straight to the Stepper Config Wizard in Section(<>). EMC has provided quick setup for the Xylotex machines. == Machine Information Gather the information about each axis of your machine. Drive timing is in nano seconds. If you're unsure about the timing many popular drives are included in the stepper configuration wizard. Note some newer Gecko drives have different timing than the original one. A list is also on the user maintained EMC2 wiki site of more drives at link:[http://wiki.linuxcnc.org]. [width="100%", options="header"] |==================================================================== |Axis | Drive Type | Step Time ns | Step Space ns | Dir. Hold ns | Dir. Setup ns |X | | | | | |Y | | | | | |Z | | | | | | | | | | | |==================================================================== == Pinout Information Gather the information about the connections from your machine to the PC parallel port. [width="100%", options="header"] |============================================================================== |Output Pin | Typ. Function | If Different | Input Pin | Typ. Function | If Different |1 | E-Stop Out | | 10 | X Limit/Home | |2 | X Step | | 11 | Y Limit/Home | |3 | X Direction | | 12 | Z Limit/Home | |4 | Y Step | | 13 | A Limit/Home | |5 | Y Direction | | 15 | Probe In | |6 | Z Step | | | | |7 | Z Direction | | | | |8 | A Step | | | | |9 | A Direction | | | | |14 | Spindle CW | | | | |16 | Spindle PWM | | | | |17 | Amplifier Enable | | | | |============================================================================== Note any pins not used should be set to Unused in the drop down box. These can always be changed later by running Stepconf again. == Mechanical Information Gather information on steps and gearing. The result of this is steps per user unit which is used for SCALE in the .ini file. [width="100%", options="header"] |============================================================================== |Axis | Steps/Rev. | Micro Steps | Motor Teeth | Leadscrew Teeth | Leadscrew Pitch |X | | | | | |Y | | | | | |Z | | | | | | | | | | | |============================================================================== *Steps per revolution* is how many stepper-motor-steps it takes to turn the stepper motor one revolution. Typical is 200. *Micro Steps* is how many CNC-output-steps the drive needs to move the stepper motor one stepper-motor-step. If microstepping is not used, this number will be 1. If microstepping is used, typical values will be near 4-16, perhaps 8 or 10. [NOTE] Smaller values don't help that much, because the approximation of the sine and cosine waves involved is too coarse. Larger values don't help by requiring too many steps from the CNC output and slowing down the maximum speed. *Motor Teeth* and *Leadscrew Teeth* is if you have some reduction (gears, chain, timing belt, etc.) between the motor and the leadscrew. If not, then set these both to 1. *Leadscrew Pitch* is how much movement occurs (in user units) in one leadscrew turn. If you're setting up in inches then it is inches per turn. If you're setting up in millimeters then it is millimeters per turn. The net result you're looking for is how many CNC-output-steps it takes to move one user unit (inches or mm). For Example (inches): Stepper = 200 steps per revolution Drive = 10 micro steps per step Motor Teeth = 20 Leadscrew Teeth = 40 Leadscrew Pitch = 0.2000 inches per turn From the above information, the leadscrew moves 0.200 inches per turn. - The motor turns 2.000 times per 1 leadscrew turn. - The drive takes 10 microstep inputs to make the stepper step once. - The drive needs 2000 steps to turn the stepper one revolution. So the scale needed is: latexmath:[ \frac{200 motor steps}{1 motor rev} \times \frac{10 microsteps}{1 motor step} \times \frac{2 motor revs}{1 leadscrew rev} \times \frac{1 leadscrew revs}{0.2000 inch} = \frac{20,000 microsteps}{inch} ] Here's another example, in millimeters this time: For Example (mm): Stepper = 200 steps per revolution Drive = 8 micro steps per step Motor Teeth = 30 Leadscrew Teeth = 90 Leadscrew Pitch = 5.00 mm per turn From the above information: - The leadscrew moves 5.00 mm per turn. - The motor turns 3.000 times per 1 leadscrew turn. - The drive takes 8 microstep inputs to make the stepper step once. - The drive needs 1600 steps to turn the stepper one revolution. So the scale needed is: latexmath:[ \frac{200 motor steps}{1 motor rev} \times \frac{8 microsteps}{1 motor step} \times \frac{3 motor revs}{1 leadscrew rev} \times \frac{1 leadscrew revs}{5.000 mm} = \frac{960 microsteps}{mm} ] == Configuration Wizard Run the Stepconf Wizard in chapter (<>) == Link on the desktop (shortcut) It is possible to create a link on the desktop after the use of Assistant Stepconf. Since the start EMC2 CNC menu and choose newly created configuration in the list. Tick "Create desktop shortcut" and confirm with OK. There is now a shortcut on the desktop that can be run directly from this configuration. == Modifying To change something in the basic configuration created by Stepconf Wizard run the wizard again. Select "Modify a Configuration", then pick the configuration file *.stepconf* you wish to modify in the emc2/configs folder. The file headers tell you if the file can be manually edited or not. // vim: set syntax=asciidoc: