tutorial.lyx

CNC 的开放码,EMC2 V2.2.8版

Owner  Type  Dir     Value      Name
\newline 
 32769    float OUT   5.19530e-01  siggen.0.cosine
\newline 
 32769    float OUT   6.73893e-01  siggen.0.sawtooth
\newline 
 32769    float OUT  -8.54452e-01  siggen.0.sine
\newline 
 32769    float OUT   1.00000e+00  siggen.0.square
\newline 
 32769    float OUT   3.47785e-01  siggen.0.triangle
\layout Standard

We did two 
\family typewriter 
show pin
\family default 
 commands in quick succession, and you can see that the outputs are no longer
 zero.
 The sine, cosine, sawtooth, and triangle outputs are changing constantly.
 The square output is also working, however it simply switches from +1.0
 to -1.0 every cycle.
\layout Subsection

Changing parameters
\layout Standard

The real power of HAL is that you can change things.
 For example, we can use the 
\family typewriter 
setp
\family default 
 command to set the value of a parameter.
 Let's change the amplitude of the signal generator from 1.0 to 5.0:
\layout LyX-Code

halcmd:
\series bold 
 setp siggen.0.amplitude 5
\series default 

\newline 
emc2$
\layout Standard

Check the parameters and pins again:
\layout LyX-Code

halcmd: setp siggen.0.amplitude 5
\newline 
halcmd: show param
\newline 
Parameters:
\newline 
Owner  Type  Dir    Value      Name
\newline 
 32769    float  RW   5.00000e+00  siggen.0.amplitude
\newline 
 32769    float  RW   1.00000e+00  siggen.0.frequency
\newline 
 32769    float  RW   0.00000e+00  siggen.0.offset
\newline 
 32769    s32    RO          397   siggen.0.update.time
\newline 
 32769    s32    RW       109100   siggen.0.update.tmax
\newline 
halcmd: show pin
\newline 
Component Pins:
\newline 
Owner  Type  Dir     Value      Name
\newline 
 32769    float OUT   4.78453e+00  siggen.0.cosine
\newline 
 32769    float OUT  -4.53106e+00  siggen.0.sawtooth
\newline 
 32769    float OUT   1.45198e+00  siggen.0.sine
\newline 
 32769    float OUT  -5.00000e+00  siggen.0.square
\newline 
 32769    float OUT   4.02213e+00  siggen.0.triangle
\layout Standard

Note that the value of parameter
\family typewriter 
 siggen.0.amplitude
\family default 
 has changed to 5.000, and that the pins now have larger values.
\layout Subsection

Saving the HAL configuration
\layout Standard

Most of what we have done with 
\family typewriter 
halcmd
\family default 
 so far has simply been viewing things with the 
\family typewriter 
show
\family default 
 command.
 However two of the commands actually changed things.
 As we design more complex systems with HAL, we will use many commands to
 configure things just the way we want them.
 HAL has the memory of an elephant, and will retain that configuration until
 we shut it down.
 But what about next time? We don't want to manually enter a bunch of commands
 every time we want to use the system.
 We can save the configuration of the entire HAL with a single command:
\layout LyX-Code

halcmd:
\series bold 
 save
\series default 

\newline 
# components
\newline 
loadrt threads name1=test-thread period1=1000000
\newline 
loadrt siggen
\newline 
# signals
\newline 
# links
\newline 
# parameter values
\newline 
setp siggen.0.amplitude  5.00000e+00
\newline 
setp siggen.0.frequency  1.00000e+00
\newline 
setp siggen.0.offset  0.00000e+00
\newline 
# realtime thread/function links
\newline 
addf siggen.0.update test-thread
\layout Standard

The output of the 
\family typewriter 
save
\family default 
 command is a sequence of HAL commands.
 If you start with an 
\begin_inset Quotes eld
\end_inset 

empty
\begin_inset Quotes erd
\end_inset 

 HAL and run all these commands, you will get the configuration that existed
 when the 
\family typewriter 
save
\family default 
 command was issued.
 To save these commands for later use, we simply redirect the output to
 a file:
\layout LyX-Code

halcmd: 
\series bold 
save all saved.hal
\layout Subsection

Restoring the HAL configuration
\layout Standard

To restore the HAL configuration stored in 
\family typewriter 
saved.hal
\family default 
, we need to execute all of those HAL commands.
 To do that, we use
\family typewriter 
 -f <filename>
\family default 
 which reads commands from a file, and 
\family typewriter 
-I
\family default 
 which shows the halcmd prompt after execiting the commands:
\layout LyX-Code

emc2$ 
\series bold 
halrun -I -f saved.hal
\layout Standard

Notice that there is not a 'start' command in saved.hal.
 It's necessary to issue it again (or edit saved.hal to add it there):
\layout LyX-Code

halcmd: 
\series bold 
start
\layout Section


\begin_inset LatexCommand \label{sec:Tutorial - Halmeter}

\end_inset 

Looking at the HAL with halmeter
\layout Standard

You can build very complex HAL systems without ever using a graphical interface.
 However there is something satisfying about seeing the result of your work.
 The first and simplest GUI tool for the HAL is halmeter.
 It is a very simple program that is the HAL equivalent of the handy Fluke
 multimeter (or Simpson analog meter for the old timers).
\layout Standard

We will use the siggen component again to check out halmeter.
 If you just finished the previous example, then siggen is already loaded.
 If not, we can load it just like we did before:
\layout LyX-Code

emc2$ 
\series bold 
halrun
\newline 

\series default 
halcmd: 
\series bold 
loadrt siggen
\newline 

\series default 
halcmd: 
\series bold 
loadrt threads name1=test-thread period1=1000000
\newline 

\series default 
halcmd: 
\series bold 
addf siggen.0.update test-thread
\newline 

\series default 
halcmd:
\series bold 
 start
\newline 

\series default 
halcmd:
\series bold 
 setp siggen.0.amplitude 5
\layout Subsection

Starting halmeter
\layout Standard

At this point we have the siggen component loaded and running.
 It's time to start halmeter.
 Since halmeter is a GUI app, X must be running.
\layout LyX-Code

halcmd: 
\series bold 
loadusr halmeter
\layout Standard

At the same time, a halmeter window opens on your screen, looking something
 like figure 
\begin_inset LatexCommand \ref{fig:Halmeter-demo-1}

\end_inset 

.
\layout Standard


\begin_inset Float figure
wide false
collapsed false

\layout Standard
\align center 

\begin_inset Graphics
	filename halmeter-demo-1.png

\end_inset 


\layout Caption


\begin_inset LatexCommand \label{fig:Halmeter-demo-1}

\end_inset 

Halmeter at startup, nothing selected
\end_inset 


\layout Subsection

Using halmeter
\layout Standard

The meter in figure 
\begin_inset LatexCommand \ref{fig:Halmeter-demo-1}

\end_inset 

 isn't very useful, because it isn't displaying anything.
 To change that, click on the 'Select' button, which will open the probe
 selection dialog (figure 
\begin_inset LatexCommand \ref{fig:Halmeter-demo-2}

\end_inset 

).
 
\layout Standard


\begin_inset Float figure
wide false
collapsed false

\layout Standard
\align center 

\begin_inset Graphics
	filename halmeter-demo-2.png

\end_inset 


\layout Caption


\begin_inset LatexCommand \label{fig:Halmeter-demo-2}

\end_inset 

Halmeter source selection dialog
\end_inset 


\layout Standard

This dialog has three tabs.
 The first tab displays all of the HAL pins in the system.
 The second one displays all the signals, and the third displays all the
 parameters.
 We would like to look at the pin 
\family typewriter 
siggen.0.triangle
\family default 
 first, so click on it then click the 'OK' button.
 The probe selection dialog will close, and the meter looks something like
 figure 
\begin_inset LatexCommand \ref{fig:Halmeter-demo-3}

\end_inset 

.
\layout Standard


\begin_inset Float figure
wide false
collapsed false

\layout Standard
\align center 

\begin_inset Graphics
	filename halmeter-demo-3.png

\end_inset 


\layout Caption


\begin_inset LatexCommand \label{fig:Halmeter-demo-3}

\end_inset 

Halmeter displaying the value of a pin
\end_inset 


\layout Standard

You should see the value changing as siggen generates its triangle wave.
 Halmeter refreshes its display about 5 times per second.
 
\layout Standard

If you want to quickly look at a number of pins, you can use the 'Accept'
 button in the source selection dialog.
 Click on 'Select' to open the dialog again.
 This time, click on another pin, like siggen.0.cosine, and then click 'Accept'.
 When you click 'Accept', the meter immediately begins to display the newly
 selected item, but the dialog does not close.
 Try displaying a parameter instead of a pin.
 Click on the 'Parameters' tab, then select a parameter and click 'Accept'
 again.
 You can very quickly move the 
\begin_inset Quotes eld
\end_inset 

meter probes
\begin_inset Quotes erd
\end_inset 

 from one item to the next with a couple of clicks.
\layout Standard

To shut down halmeter, just click the exit button.
\layout Standard

If you want to look at more than one pin, signal, or parameter at a time,
 you can just start more halmeters.
 The halmeter window was intentionally made very small so you could have
 a lot of them on the screen at once.
 
\begin_inset Foot
collapsed true

\layout Standard

Halmeter is due for a rewrite.
 The rewrite will do a number of things to make it nicer.
 Scientific notation will go away - it is a pain to read.
 Some form of ranging (including autoranging) will be added to allow it
 to display a wide range of numbers without using scientific notation.
 An 
\begin_inset Quotes eld
\end_inset 

analog bar graph
\begin_inset Quotes erd
\end_inset 

 display will also be added to give a quick indication of trends.
 When the rewrite is done, these screenshots and the accompanying text will
 be revised to match the new version.
\end_inset 


\layout Standard


\begin_inset ERT
status Collapsed

\layout Standard

\backslash 
clearpage
\end_inset 


\layout Section


\begin_inset LatexCommand \label{sec:Tutorial - More Complex}

\end_inset 

A slightly more complex example.
\layout Standard

Up till now we have only loaded one HAL component.
 But the whole idea behind the HAL is to allow you to load and connect a
 number of simple components to make up a complex system.
 The next example will use two components.
\layout Standard

Before we can begin building this new example, we want to start with a clean
 slate.
 If you just finished one of the previous examples, we need to remove the
 all components and reload the RTAPI and HAL libraries:
\layout LyX-Code

halcmd: 
\series bold 
exit
\newline 

\series default 
emc2$ 
\series bold 
halrun
\layout Subsection

Installing the components
\layout Standard

Now we are going to load the step pulse generator component.
 For a detailed description of this component refer to section 
\begin_inset LatexCommand \ref{sec:Stepgen}

\end_inset 

.
 For now, we can skip the details, and just run the following commands:
\begin_inset Foot
collapsed true

\layout Standard

The 
\begin_inset Quotes eld
\end_inset 


\backslash 

\begin_inset Quotes erd
\end_inset 

 at the end of a long line indicates line wrapping (needed for formatting
 this document).
 When entering the commands at the command line, simply skip the 
\begin_inset Quotes eld
\end_inset 


\backslash 

\begin_inset Quotes erd
\end_inset 

 (do not hit enter) and keep typing from the following line.
\end_inset 


\layout LyX-Code

halrun: 
\series bold 
loadrt freqgen step_type=0,0
\newline 

\series default 
halcmd:
\series bold 
 loadrt siggen
\newline 

\series default 
halcmd:
\series bold 
 loadrt threads name1=fast fp1=0 period1=50000 name2=slow period2=1000000
\layout Standard

The first command loads two step generators, both configured to generate
 stepping type 0.
 The second command loads our old friend siggen, and the third one creates
 two threads, a fast one with a period of 50 micro-seconds and a slow one
 with a period of 1mS.
 The fast thread doesn't support floating point functions.
\layout Standard

As before, we can use 
\family typewriter 
halcmd show
\family default 
 to take a look at the HAL.
 This time we have a lot more pins and parameters than before:
\layout LyX-Code

halcmd:
\series bold 
 show pin
\newline 

\series default 
Component Pins:
\newline 
Owner  Type  Dir    Value      Name
\newline 
 03    float -W   0.00000e+00  siggen.0.cosine
\newline 
 03    float -W   0.00000e+00  siggen.0.sawtooth
\newline 
 03    float -W   0.00000e+00  siggen.0.sine
\newline 
 03    float -W   0.00000e+00  siggen.0.square
\newline 
 03    float -W   0.00000e+00  siggen.0.triangle
\newline 
 02    s32   -W            0   freqgen.0.counts
\newline 
 02    bit   -W     FALSE      freqgen.0.dir
\newline 
 02    float -W   0.00000e+00  freqgen.0.position
\newline 
 02    bit   -W     FALSE      freqgen.0.step
\newline 
 02    float R-   0.00000e+00  freqgen.0.velocity
\newline 
 02    s32   -W            0   freqgen.1.counts
\newline 
 02    bit   -W     FALSE      freqgen.1.dir
\newline 
 02    float -W   0.00000e+00  freqgen.1.position
\newline 
 02    bit   -W     FALSE      freqgen.1.step
\newline 
 02    float R-   0.00000e+00  freqgen.1.velocity
\newline 
halcmd:
\series bold 
 show param
\newline 

\series default 
Parameters:
\newline 
Owner  Type  Dir    Value      Name
\newline 
 03    float  -W   1.00000e+00  siggen.0.amplitude
\newline 
 03    float  -W   1.00000e+00  siggen.0.frequency
\newline 
 03    float  -W   0.00000e+00  siggen.0.offset
\newline 
 02    u32    -W     000000001  freqgen.0.dirhold
\newline 
 02    u32    -W     000000001  freqgen.0.dirsetup
\newline 
 02    float  R-   0.00000e+00  freqgen.0.frequency
\newline 
 02    float  -W   0.00000e+00  freqgen.0.maxaccel
\newline 
 02    float  -W   1.00000e+15  freqgen.0.maxfreq
\newline 
 02    float  -W   1.00000e+00  freqgen.0.position-scale
\newline 
 02    s32    R-            0   freqgen.0.rawcounts
\newline 
 02    u32    -W     000000001  freqgen.0.steplen
\newline 
 02    u32    -W     000000001  freqgen.0.stepspace
\newline 
 02    float  -W   1.00000e+00  freqgen.0.velocity-scale
\newline 
 02    u32    -W     000000001  freqgen.1.dirhold
\newline 
 02    u32    -W     000000001  freqgen.1.dirsetup
\newline 
 02    float  R-   0.00000e+00  freqgen.1.frequency
\newline 
 02    float  -W   0.00000e+00  freqgen.1.maxaccel
\newline 
 02    float  -W   1.00000e+15  freqgen.1.maxfreq
\newline 
 02    float  -W   1.00000e+00  freqgen.1.position-scale
\newline 
 02    s32    R-            0   freqgen.1.rawcounts
\newline 
 02    u32    -W     000000001  freqgen.1.steplen
\newline 
 02    u32    -W     000000001  freqgen.1.stepspace
\newline 
 02    float  -W   1.00000e+00  freqgen.1.velocity-scale
\layout Subsection

Connecting pins with signals
\layout Standard

What we have is two step pulse generators, and a signal generator.
 Now it is time to create some HAL signals to connect the two components.
 We are going to pretend that the two step pulse generators are driving
 the X and Y axis of a machine.
 We want to move the table in circles.
 To do this, we will send a cosine signal to the X axis, and a sine signal
 to the Y axis.
 The siggen module creates the sine and cosine, but we need 
\begin_inset Quotes eld
\end_inset 

wires
\begin_inset Quotes erd
\end_inset 

 to connect the modules together.
 In the HAL, 
\begin_inset Quotes eld
\end_inset 

wires
\begin_inset Quotes erd
\end_inset 

 are called signals.
 We need to create two of them.