rtcomps.lyx

CNC 的开放码,EMC2 V2.2.8版

\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.FF0
\family default 
 -- Zeroth order feedforward - output proportional to command (position).
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.FF1
\family default 
 -- First order feedforward - output proportional to derivative of command
 (velocity).
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.FF2
\family default 
 -- Second order feedforward - output proportional to 2nd derivative of
 command (acceleration)
\begin_inset Foot
collapsed true

\layout Standard

FF2 is not currently implemented, but it will be added.
 Consider this note a 
\begin_inset Quotes eld
\end_inset 

FIXME
\begin_inset Quotes erd
\end_inset 

 for the code
\end_inset 

.
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.deadband
\family default 
 -- Amount of error that will be ignored 
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.maxerror
\family default 
 -- Limit on error 
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.maxerrorI
\family default 
 -- Limit on error integrator 
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.maxerrorD
\family default 
 -- Limit on error derivative 
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.maxcmdD
\family default 
 -- Limit on command derivative 
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.maxcmdDD
\family default 
 -- Limit on command 2nd derivative 
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.maxoutput
\family default 
 -- Limit on output value
\layout Standard

All of the 
\family typewriter 
max ???
\family default 
 limits are implemented such that if the parameter value is zero, there
 is no limit.
\layout Standard

If 
\family typewriter 
debug=1
\family default 
 was specified when the component was installed, four additional parameters
 will be exported:
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.errorI
\family default 
 -- Integral of error.
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.errorD
\family default 
 -- Derivative of error.
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.commandD
\family default 
 -- Derivative of the command.
\layout Itemize


\family typewriter 
\noun on 
(float)
\noun default 
 pid.<loopnum>.commandDD
\family default 
 -- 2nd derivative of the command.
 
\layout Subsection

Functions
\layout Standard

The component exports one function for each PID loop.
 This function performs all the calculations needed for the loop.
 Since each loop has its own function, individual loops can be included
 in different threads and execute at different rates.
 
\layout Itemize


\family typewriter 
\noun on 
(funct)
\noun default 
 pid.<loopnum>.do_pid_calcs
\family default 
 -- Performs all calculations for a single PID loop.
\layout Standard

If you want to understand the exact algorithm used to compute the output
 of the PID loop, refer to figure 
\begin_inset LatexCommand \ref{fig:PID-block-diag}

\end_inset 

, the comments at the beginning of
\family typewriter 
 emc2/src/hal/components/pid.c
\family default 
, and of course to the code itself.
 The loop calculations are in the C function
\family typewriter 
 calc_pid()
\family default 
.
\layout Standard


\begin_inset ERT
status Collapsed

\layout Standard

\backslash 
clearpage
\end_inset 


\layout Section


\begin_inset LatexCommand \label{sec:Simulated-Encoder}

\end_inset 

Simulated Encoder
\begin_inset LatexCommand \index{sim-encoder}

\end_inset 


\layout Standard

The simulated encoder is exactly that.
 It produces quadrature pulses with an index pulse, at a speed controlled
 by a HAL pin.
 Mostly useful for testing.
\layout Subsection

Installing
\layout LyX-Code

emc2$ 
\series bold 
halcmd loadrt sim-encoder num_chan=<number>
\layout Standard


\family typewriter 
<number>
\family default 
 is the number of encoders that you want to simulate.
 If not specified, one encoder will be installed.
 The maximum number is 8 (as defined by MAX_CHAN in sim_encoder.c).
 
\layout Subsection

Removing
\layout LyX-Code

emc2$ 
\series bold 
halcmd unloadrt sim-encoder
\layout Subsection

Pins
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
sim-encoder.<chan-num>.speed
\family default 
 -- The speed command for the simulated shaft.
\layout Itemize


\family typewriter 
\noun on 
(bit) 
\noun default 
sim-encoder.<chan-num>.phase-A
\family default 
 -- Quadrature output.
\layout Itemize


\family typewriter 
\noun on 
(bit) 
\noun default 
sim-encoder.<chan-num>.phase-B
\family default 
 -- Quadrature output.
\layout Itemize


\family typewriter 
\noun on 
(bit) 
\noun default 
sim-encoder.<chan-num>.phase-Z
\family default 
 -- Index pulse output.
 
\layout Standard

When 
\family typewriter 
.speed
\family default 
 is positive, 
\family typewriter 
.phase-A
\family default 
 leads 
\family typewriter 
.phase-B
\family default 
.
\layout Subsection

Parameters
\layout Itemize


\shape smallcaps 
\noun on 
(u32)
\family typewriter 
\shape default 
\noun default 
 sim-encoder.<chan-num>.ppr
\family default 
 -- Pulses Per Revolution.
\layout Itemize


\shape smallcaps 
\noun on 
(float)
\family typewriter 
\shape default 
\noun default 
 sim-encoder.<chan-num>.scale
\family default 
 -- Scale Factor for 
\family typewriter 
\series bold 
speed
\family default 
\series default 
.
 The default is 1.0, which means that 
\family typewriter 
\series bold 
speed
\family default 
\series default 
 is in revolutions per second.
 Change to 60 for RPM, to 360 for degrees per second, 6.283185 for radians
 per seconed, etc.
\layout Standard

Note that pulses per revolution is not the same as counts per revolution.
 A pulse is a complete quadrature cycle.
 Most encoder counters will count four times during one complete cycle.
\layout Subsection

Functions
\layout Standard

The component exports two functions.
 Each function affects all simulated encoders.
\layout Itemize


\family typewriter 
\noun on 
(funct)
\noun default 
 sim-encoder.make-pulses
\family default 
 -- High speed function to generate quadrature pulses (no floating point).
\layout Itemize


\family typewriter 
\noun on 
(funct)
\noun default 
 sim-encoder.update-speed
\family default 
 -- Low speed function to read 
\family typewriter 
\series bold 
speed
\family default 
\series default 
, do scaling, and set up 
\family typewriter 
\series bold 
make-pulses
\family default 
\series default 
.
\layout Standard


\begin_inset ERT
status Collapsed

\layout Standard

\backslash 
clearpage
\end_inset 


\layout Section


\begin_inset LatexCommand \label{sec:Debounce}

\end_inset 

Debounce
\begin_inset LatexCommand \index{debounce}

\end_inset 


\layout Standard

Debounce is a realtime component that can filter the glitches created by
 mechanical switch contacts.
 It may also be useful in other applications where short pulses are to be
 rejected.
\layout Subsection

Installing
\layout LyX-Code

emc2$ 
\series bold 
halcmd loadrt debounce cfg=
\begin_inset Quotes erd
\end_inset 

<config-string>
\begin_inset Quotes erd
\end_inset 


\layout Standard


\family typewriter 
<config-string>
\family default 
 is a series of space separated decimal integers.
 Each number installs a group of identical debounce filters, the number
 determines how many filters are in the group.
 For example:
\layout LyX-Code

emc2$ 
\series bold 
halcmd loadrt debounce cfg=
\begin_inset Quotes erd
\end_inset 

1 4 2
\begin_inset Quotes erd
\end_inset 


\layout Standard

will install three groups of filters.
 Group 0 contains one filter, group 1 contains four, and group 2 contains
 two filters.
 The default value for 
\family typewriter 
<config-string>
\family default 
 is 
\family typewriter 

\begin_inset Quotes eld
\end_inset 

1
\begin_inset Quotes erd
\end_inset 


\family default 
 which will install a single group containing a single filter.
 The maximum number of groups 8 (as defined by MAX_GROUPS in debounce.c).
 The maximum number of filters in a group is limited only by shared memory
 space.
 Each group is completely independent.
 All filters in a single group are identical, and they are all updated by
 the same function at the same time.
 In the following descriptions, 
\family typewriter 
<G>
\family default 
 is the group number and 
\family typewriter 
<F>
\family default 
 is the filter number within the group.
 The first filter is group 0, filter 0.
\layout Subsection

Removing
\layout LyX-Code

emc2$ 
\series bold 
halcmd unloadrt debounce
\layout Subsection

Pins
\layout Standard

Each individual filter has two pins.
\layout Itemize


\family typewriter 
\noun on 
(bit) 
\noun default 
debounce.<G>.<F>.in
\family default 
 -- Input of filter 
\family typewriter 
<F>
\family default 
 in group 
\family typewriter 
<G>
\family default 
.
\layout Itemize


\family typewriter 
\noun on 
(bit) 
\noun default 
debounce.<G>.<F>.out
\family default 
 -- Output of filter 
\family typewriter 
<F>
\family default 
 in group 
\family typewriter 
<G>
\family default 
.
\layout Subsection

Parameters
\layout Standard

Each group of filters has one parameter
\begin_inset Foot
collapsed true

\layout Standard

Each individual filter also has an internal state variable.
 There is a compile time switch that can export that variable as a parameter.
 This is intended for testing, and simply wastes shared memory under normal
 circumstances.
\end_inset 

.
 
\layout Itemize


\family typewriter 
\noun on 
(s32) 
\noun default 
debounce.<G>.delay
\family default 
 -- Filter delay for all filters in group 
\family typewriter 
<G>
\family default 
.
\layout Standard

The filter delay is in units of thread periods.
 The minimum delay is zero.
 The output of a zero delay filter exactly follows its input - it doesn't
 filter anything.
 As 
\family typewriter 
delay
\family default 
 increases, longer and longer glitches are rejected.
 If 
\family typewriter 
delay
\family default 
 is 4, all glitches less than or equal to four thread periods will be rejected.
\layout Subsection

Functions
\layout Standard

Each group of filters has one function, which updates all the filters in
 that group 
\begin_inset Quotes eld
\end_inset 

simultaneously
\begin_inset Quotes erd
\end_inset 

.
 Different groups of filters can be updated from different threads at different
 periods.
\layout Itemize


\family typewriter 
\noun on 
(funct)
\noun default 
 debounce.<G>
\family default 
 -- Updates all filters in group 
\family typewriter 
<G>
\family default 
.
\layout Section


\begin_inset LatexCommand \label{sec:Siggen}

\end_inset 

Siggen
\begin_inset LatexCommand \index{siggen}

\end_inset 


\layout Standard

Siggen is a realtime component that generates square, triangle, and sine
 waves.
 It is primarily used for testing.
 
\layout Subsection

Installing
\layout LyX-Code

emc2$ 
\series bold 
halcmd loadrt siggen [num_chan=<chans>]
\layout LyX-Code

\layout Standard


\family typewriter 
<chans>
\family default 
 is the number of signal generators that you want to install.
 If 
\family typewriter 
numchan
\family default 
 is not specified, one signal generator will be installed.
 The maximum number of generators is 16 (as defined by MAX_CHAN in siggen.c).
 Each generator is completely independent.
 In the following descriptions, 
\family typewriter 
<chan>
\family default 
 is the number of a specific signal generator (the numbers start at 0).
\layout Subsection

Removing
\layout LyX-Code

emc2$ 
\series bold 
halcmd unloadrt siggen
\layout Subsection

Pins
\layout Standard

Each generator has five output pins.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.sine
\family default 
 -- Sine wave output.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.cosine
\family default 
 -- Cosine output.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.sawtooth
\family default 
 -- Sawtooth output.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.triangle
\family default 
 -- Triangle wave output.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.square
\family default 
 -- Square wave output.
\layout Standard

All five outputs have the same frequency, amplitude, and offset.
\layout Standard

In addition to the output pins, there are three control pins:
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.frequency
\family default 
 -- Sets the frequency in Hertz, default value is 1 Hz.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.amplitude
\family default 
 -- Sets the peak amplitude of the output waveforms, default is 1.
\layout Itemize


\family typewriter 
\noun on 
(float) 
\noun default 
siggen.<chan>.offset
\family default 
 -- Sets DC offset of the output waveforms, default is 0.
\layout Standard

For example, if 
\family typewriter 
siggen.0.amplitude
\family default 
 is 1.0 and 
\family typewriter 
siggen.0.offset
\family default 
 is 0.0, the outputs will swing from -1.0 to +1.0.
 If 
\family typewriter 
siggen.0.amplitude
\family default 
 is 2.5 and 
\family typewriter 
siggen.0.offset
\family default 
 is 10.0, then the outputs will swing from 7.5 to 12.5.
\layout Subsection

Parameters
\layout Standard

None.
 
\begin_inset Foot
collapsed true

\layout Standard

Prior to version 2.1, frequency, amplitude, and offset were parameters.
 They were changed to pins to allow control by other components.
\end_inset 


\layout Subsection

Functions
\layout Itemize


\family typewriter 
\noun on 
(funct)
\noun default 
 siggen.<chan>.update
\family default 
 -- Calculates new values for all five outputs.
\the_end