Pd Documentation 3

- - -Pd Documentation chapter 3: Getting Pd to run - -
- back to table of contents + + Pd Documentation 3 + + + + + + + +

Pd Documentation chapter 3: Getting Pd to run

+ +

+ back to table of contents

+

-Pd runs under Irix, Microsoft Windows, Linux, and Mac OS 10.2 (Jaguar). +

Pd runs under Irix, Microsoft Windows, Linux, and MacOS 10.2 (Jaguar). How to get Pd up and running depends on your operating system, but the overall strategy is the same. You must first get and install it, and then untangle whatever problems arise in handling audio and MIDI input and output, and finally get Pd to meet its real-time obligations reliably. +

Installation instructions are platform-specfic; the following four +sections +will describe what to do for various operating systems you might have. In case of trouble also consult the Pd mailing list archive on http://iem.kug.ac.at/mailinglists/pd-list/ , which often has late-breaking news about configuration problems and solutions. +The rest of this section describes how to get audio and MIDI to work. +

+To test audio and MIDI, start Pd and select "test Audio and MIDI" from the +"Media" menu. You should see a window like this: + +

+ test tone patch +

+ +

First, try to get Pd to play a sine wave over your speakers. The "TEST +TONE" control at top left turns this on and off. Normally, all the output +channels are turned on so that when you turn the tone on (to a soft -40 dB or a +louder -20 dB) you should get output on the first six of your output channels. +(If you have fewer than six output channnels open, the extra +channels aren't played; and if you have more, this particular patch won't +use them.) + +

If there's anything wrong, the most likely outcome is that you will hear +nothing at all. This could be for any of at least three reasons: Pd might +have failed to open the audio device; the audio card's output volume might +be set to zero; or your audio system might not be set to amplify the computer +output. + +

The number boxes labeled "AUDIO INPUT" show the levels of incoming +audio, in dB, with 100 being maximum. (Incoming signals may clip at +RMS levels below 100; for instance, a sinusoid clips at about 97 dB.) +Any DC present in the input (such as you get with cheap audio hardware) +will show up as level unless you turn on the "input hipass" toggle +at right; then the DC component is filtered out before metering. + +

To test the quality of audio input and output, turn on "monitor" +(also at right) which causes the inputs to be played to the outputs at +unit gain. You should hear a faithful, non-distored copy of whatever is +sent through the patch. + +

It is easy to get two copies of Pd running by accident; on most machines +only one at a time may be inputting and outputting sound. (Some copy of Pd +might have audio or MIDI devices open and prevent the copy you're trying to use +from getting access to them.) Having extra +copies of Pd around will also eat CPU cycles uselessly.

You may be interested in getting only audio output or audio input, or you may need both to run simultaneously. By default, Pd will try to run both, but if you don't need either input or output, you may find that Pd runs more reliably, or at least more efficiently, with the unused direction -turned off. This is controlled by Pd's command line flags. +turned off. This may be specified in Pd's command line flags or using the +"audio settings" dialog panel.

Depending on your application you will have a more or less stringent latency @@ -43,141 +91,66 @@ inevitable occasions where the CPU runs off to service some different task from Pd. How small this latency can be chosen depends on your OS and your audio driver. -

-To test audio and MIDI, start Pd and select "test Audio and MIDI" from the -"help" menu. -

TIP: If Pd starts up but you get distortion or glitches in the audio output, this could be either because the "audio I/O buffer" isn't big enough, or else because the CPU load of the patch you're running is too great for the machine you have, or else because the ADC and DAC are out of sync or even at different sample rates. To test for the first possibility, try increasing the -"-audiobuf" parameter in the command line (but see also under your OS below.) -For the second, start up your favorite performance monitor program; and for the -third, try starting Pd up with ADCs disabled. - -

Here are instructions for getting and installing Pd for the four -operating systems it runs on: IRIX, MS Windows, Linux, and Max OSX. - -

3.1. IRIX (SGI machines)

- -

(NOTE: as of release 0.35 I haven't had an IRIX machine to compile -Pd on. Soeren Bovbjerg has kindly compiled 0.35 and 0.36 for IRIX; -you can find these at - http://www.cvmt.dk/~sb/. ) - -

Download Pd, which will be a "tar.Z" file. You can unpack this by -typing "zcat [name].tar.Z | tar xf -" to a shell. This creates a directory -named "pd". - -

-Starting with release 0.25, Pd should come in "n32" and "o32" versions. -"o32" is the default and will run on IRIX 5.x and up. "n32" runs faster, -but only on 6.x and up. Also, "externs" have to be updated for n32. The -"pd" executable (bin/pd in the distribution) is a symbolic link to either -"pd-o32" or "pd-n32." - -

NOTE: "externs" appear to be broken in the N32 version... I'm not sure -how long this has been true. If you want to use external objects, you have -to use the O32 version. - -

-Please note that the path to the Pd executable program can't contain -space characters; don't put it in a directory named "Program Files" -for example. - -

-If for example you put Pd in ~, the executable program -will be ~/pd/bin/pd. The program looks at its command line to -figure out where it is, so it's best to invoke Pd by its full pathname. -You should always invoke Pd from a Unix shell because many important -messages appear on the standard error. - -

-The simplest way to invoke Pd is to -make an alias in your ".cshrc" file (assuming you use the "c" shell) such as: -

-
-    alias pd ~/pd/bin/pd
-
-

-(assuming your Pd distribution landed in ~, for example). - -

-Pd will open the "default" audio input and output devices, without regard -for whether they are in sync or not. This will be bad if they aren't; use -the "-noadc" or "-nodac" flag to disable either the input or output. Pd is -supposed to handle up to 8 channels of audio in and/or out. (But at least -one user had to recompile Pd on his Onyx to get 8 channels working.) - -

-As to MIDI, Pd simply attempts to open all available MIDI devices for input and -output, which is probably very bad on anything more recent than my Indy. If -any MIDI ports fail to open either for input or output, all MIDI is disabled. - -

Pd has not been fixed to request real-time priority from Irix; it will -compete with all other processes on your machine for CPU time. - -

Audio and MIDI in IRIX

- -

-Pd takes command line arguments to set the number of input and output channels -and the sample rate. These don't affect the SGI's audio settings, which you -have to set separately using the "audio panel." Pd does detect the audio -sample rate if you don't specify one on the command line. - -

-On SGI machines, you have to work to get MIDI running. Before you start Pd, verify -that least one MIDI port is configured open. Pd opens the FIRST MIDI port -that's open. You might want to get rid of the "software" MIDI port if you're -running 6.x. On Indys, the usual practice is to open serial port number 2 -because some systems configure port 1 as "console" by default. You can use the -GUI if you want, or else just type -

-
-    startmidi -d /dev/ttyd2
-
-

-to get port 2 speaking MIDI, and -

-
-    stopmidi
-
-

-to stop it. You can test whether MIDI is configured by typing, -

-
-    ps -dafe | grep midi
-
-

-and looking for "startmidi" processes. -

-It's a good idea to connect your serial port to your MIDI interface before -typing the "startmidi" command, not afterward, at least in 5.x. We use the -Opcode Studio 3 interface but in principle any Mac-compatible one should work. - -

-The O2 apparently has RS232 ports, not RS422. I think SGI's web site says -something about how to deal with this. - -

3.2. Microsoft Windows

- -

Pd is compiled under NT, but shoould work under any version of Windows -since 95. Pd will appear as a "zip" file. Unzip this, creating a directory -such as \pd. (You can put it wherever you like but the path should have no -spaces in it; so "Program Files" would be a bad place.) +audio latency in the command line or the "audio settings" dialog (but see also +under your OS below.) For the second, start up your favorite performance +monitor program; and for the third, try starting Pd up with ADCs disabled. + +

In addition to the "test audio and MIDI" patch, the "Media" menu +contains items for controlling audio and MIDI settings. The first two +items, "Audio on" and "Audio off", open or close the audio devices and +start or stop Pd's audio computation. + +

If there is a choice of +audio API to make, the Media menu will display them. (On Linux, they are +OSS, ALSA, and Portaudio; on Windows, you get MMIO and ASIO). More information +about the APIs appears in the sections below. + +

Next is the "Audio settings..." menu item, which opens a dialog like this: + +

+ audio settings dialog +

+ +The exact choices you get depend on the operating system and API. The sample +rate controls both audio output and input. The audio throughput delay is +the nominal amount of time, in milliseconds, that a sound coming into the +audio input will be delayed if it is copied through Pd straight to the +output. Naturally you would like this to be as small as possible, but, +depending on OS, API, and even the specific choice of audio hardware, there +will be a limit to how small you can make this. You can typically get +10 msec on linux (and lower still if you use special tricks), 30 msec on Mac +OSX, and 60 msec on Windows (but note that there might be ways that a +patient Windows user can reduce this). + +

Next you get a choice of input and output device. If you want to open +more than one, hit "use multiple devices" and you'll be allowed up to 4 +in and 4 out. Each audio device is 2 channels by default, but you may +specify more if your hardware supports it. + +

3.1. Installing Pd in Microsoft Windows

+ +

Pd is compiled under NT, but should work under any version of Windows since +95. Pd will appear as a self-extracting archive (a ".exe" file). Run this and +select a destination directory when prompted, such as "\pd" or "Program +Files\pd".

-If for example you put Pd in C:\pd, the executable program will be -C:\pd\bin\pd. You can simply adjust your path to include C:\pd\bin and just -invoke "pd" in a command prompt window. You can also make a "command prompt" -shortcut to start Pd. +If for example you put Pd in "C:Program Files\pd", the executable program will be +"C:Program Files\pd\bin\pd". You can simply adjust your path to include +C:\pd\bin and then +invoke "pd" in a command prompt window. You can also make a shortcut to the +executable program (left-click on it and drag to the desktop, for example.)

Pd requires "TCP/IP networking" to be turned on. This doesn't mean you have to be on a real network, but simply that Pd actually consists of two -programs that make a "network link" to intercommunicate. +programs that make a "network link" (locally) to intercommunicate. -

The vanishing window

Pd is a "command line" program. Most error and diagnostic messages from Pd appear on the command prompt window Pd runs from. @@ -189,31 +162,39 @@ print an error and exit. You won't see this error unless you arrange for the to do this is to make a "batch" file ("run.bat", say) containing the Pd command line. -

Audio in Microsoft Windows

You can ask for a list of audio and MIDI devices by typing "pd -listdev"; you can then specify which audio and MIDI device to use. Type "pd -help" (or make any mistake) to get the syntax for specifying -which device to use. +which device to use. You can modify the Pd shortcut (or batch file) to +set these.

-Most PC sound cards seem to have MIDI built in; you don't seem to have to -do anything special to get Pd to send and receive MIDI. You can list and -choose MIDI devices in the same way as audio. +Alternatively, (and especially when just starting out) you can experiment +with different audio configurations using the "audio settings" +item in the Media menu. + +

+You can list and +choose MIDI devices in the same way as audio; note that, by default, MIDI +input is disabled in Windows (because it's possible to hang up some MIDI +devices if Pd exits unexpectedly).

MIDI timing is very poor if you are using simultaneous audio input and output; if you suppress either audio input or output things will improve somewhat under NT; you can apparently get the jitter down to ~40 msec. On W95 performance is simply terrible. W98, with either audio input or output suppressed, offers -fairly good MIDI timing (~5 msec jitter) but crashes occasionally. +fairly good MIDI timing (~5 msec jitter). The "first edition" used to crash +occasionally; this might be fixed in the "second edition".

Some NT and W98 drivers greet you with a constant trail of "resyncing audio" messages. Sometimes you can fix this by invoking Pd with the "-noresync" flag. -

ASIO

As of version 0.35 Pd supports ASIO. Invoke Pd as "pd -asio" and, if needed, specify "-sounddev" (etc.) flags to specify which device (see @@ -222,58 +203,19 @@ from the default (256 samples) and "-audiobuf" in milliseconds. Pd will round this down to a power of two buffers, each of "-blocksize" in sample frames. -

Using an RME Hammerfall, and specifying "-audiobuf 5 -blocksize 32" I -was able to get about 7 milliseconds of throughput delay (as measured by -the latency-measurement patch in 7.stuff/tools.) As always, you can specify -"-channels" to any even number up to the maximum (32, I think) or can specify -channel count separately for input and output (-inchannels and -outchannels). - -

The special joys of Windows 95

- -

-On Windows 95 you can expect a hard time. Every user who tries it seems to -encounter a new problem. The best way to run Pd is to get into the "MSDOS -Prompt" program and type \pb\bin\pd to it (or whatever the path ends up being.) -You can probably put pd's "bin" directory in your path so that you just type -"pd" to the prompt. - -

-You don't want to run Pd from the "run" menu because if it fails to start up -the window holding the error message will disappear instantly. Ditto for -clicking on "batch files" or on the Pd executable itself. - -

-The most common reason Pd might fail to start up in W95 is not having -"networking" turned on. Pd is actually two programs that establish an IP -interconnection. Beware that this sometimes fools Windows into calling your -ISP for no reason. - -

-It is often necessary to specify a huge audio buffer to get steady audio -output in W95; see the command line arguments below. - -

3.3. Linux

3.2. Installing Pd in Linux

What to do depends on which flavor of Linux you are running (e.g., Debian or Red Hat). The instructions here should work for Pd 0.33 and up regardless of -your situation. (If not, you can read the Pd mailing list archives for -recent problems; if you have found a new problem you're welcome to post it +your situation. (If not, you can read the Pd mailing list archives for +recent problems; if you have found a new problem you're welcome to post it to the list.) -

Before you start, you might want to check that you have the resources Pd -needs. The main things you need are the C compiler, X windows (including -the X development package for Pd to link against) and TK. If you're running -Redhat or Mandrake 7.x or up, I think these are all present by default. -The RedHat X client developer "RPM" package is called XFree86-devel. - -

You don't absolutely have to have the X server package running; you can run -Pd on the microprocessor in your refrigerator as long as it can connect to an X -server on another machine. - -

If you're running RedHat you might want to use RPM to install Pd. For -other linux distributions, download the "tar.gz" version and compile it. +

If you're running RedHat or Mandrake you might want to use RPM to install +Pd. For other linux distributions, download the "tar.gz" version and compile +Pd. -

Getting Pd as an RPM

Download Pd, perhaps from @@ -288,7 +230,13 @@ the directory containing the file, and type the command,

(substituting the real file name.) Then you should be able to type "pd" to a shell and watch the Pd main window appear. -

Getting Pd as a .tar.gz

+ +

Before you start, you might want to check that you have the resources Pd +needs. The main things you need are the C compiler, X windows (including +the X development package for Pd to link against) and TK. If you're running +Redhat or Mandrake 7.x or up, I think these are all present by default. +The RedHat X client developer "RPM" package is called XFree86-devel.

Download Pd, perhaps from @@ -300,20 +248,22 @@ the directory containing the file, and type the command,

     zcat pd-linux-033.tar.gz | tar xf -

-which creates a directory named "pd". I do this from my home directory. +

which creates a directory named "pd". I do this from my home directory. Next, compile it. "CD" to pd and read the INSTALL.txt, or else just cd to "pd/src" and type +

./configure
make depend
make +

You can pass flags to "configure" to customize your compilation:

-    To enable ALSA 0.9x (the latest one), add "--enable-alsa".
-    To enable the older ALSA 0.5x, add "--enable-old-alsa". 
-    To enable Ritsch's RME 9652 driver, add --enable-rme".
+    To enable debugging (and losing code optimization) add "--enable-debug".
+    To enable ALSA 0.9x or up, add "--enable-alsa".
+    To use Portaudio version 19 (experimental), add "--enable-portaudio".
     To put Pd in /usr/bin instead of /usr/local/bin, add "--prefix=/bin".

@@ -322,18 +272,20 @@ to "pd/src" and type

Alternatively, as superuser, you can run "make install" after "make depend" and then anyone on your system can just type "pd" to run it. -

Testing audio and MIDI.

Next try audio. We want to know whether audio output works, whether audio -input works, and whether they work simultaneously. First run "aumix" to -see audio input and output gains and which device is "recording". +input works, and whether they work simultaneously. First run "aumix" (or +any newer audio mixer app) to +check audio input and output gains and learn which input (mic; line; +etc.) is "recording". Then test audio output by running

     pd -noadc

-and selecting "test audio and MIDI" from the "help" menu. You should see a -patch. Turn on the test tone and listen. Do the usual where's-the-signal +

and selecting "test audio and MIDI" from the "Media" menu. You should see +a patch. Turn on the test tone and listen. Do the usual where's-the-signal business.

@@ -341,7 +293,7 @@ Then quit Pd and test audio input via

     pd -nodac

-Re-open the test patch and hit "meter"; look at the levels. 100 dB is a +

Re-open the test patch and hit "meter"; look at the levels. 100 dB is a hard clip; arrange gains so that the input signal tops out around 80 or 90, but no higher. @@ -352,12 +304,12 @@ hand there's no complaint, and if the audio test patch does what you want, you might wish to experiment with the "-audiobuffer" flag to see what values of audio latency your audio system can handle. -

Audio hardware in Linux

Be forewarned: installing and testing audio and MIDI drivers in Linux can take days or weeks. There apears to be no single place where you can get detailed -information on Linux audio. +information on Linux audio.

Depending on your hardware and software, you might or might not be able to @@ -375,20 +327,10 @@ releases. You can get ALSA from http://www.alsa-project.org/ . -

-(There is also a commercial version of the OSS drivers which costs $30 (slightly -more for certain audio cards.) Hit - - - http://www.opensound.com/ . - -These might be easier to use than the free OSS drivers, but I've never tried -them.) -

ALSA is able to emulate OSS, so that you can usually run Pd using the default "OSS" settings even if it's actually ALSA that's running. -

Installing and configuring FREE OSS

OSS is really a collection of loadable device drivers. The commands @@ -409,14 +351,16 @@ soundlow 1 [sound] 0 aic7xxx 23 2 -then OSS is running, and if all you see is: + +

then OSS is running, and if all you see is: +

 
 eepro100           3            1 (autoclean)
 aic7xxx           23            2

-then it isn't. You can turn OSS off by running "rmmod" repeatedly, starting +

then it isn't. You can turn OSS off by running "rmmod" repeatedly, starting with "opl3" (or whatever) so as not to remove any module before you remove all the modules that depend on it. In the above listing, "opl3*" is device dependent and you might see different names. @@ -440,7 +384,7 @@ alias sound-slot-1 es1371 -Here the two sound cards are the (motherboard resident) i810 driver and an +

Here the two sound cards are the (motherboard resident) i810 driver and an ensoniq es1371.

In RedHat at least, the "sndconfig" program tries to automatically search @@ -452,14 +396,14 @@ often not the one you want to use! two, but the majority of drivers, even for new sound cards, only support "block." Pd makes "block" the default. -

ALSA (Advanced Linux Sound Architecture)

ALSA is newer, hence less stable and harder to use, than OSS. Alsa comes in a "finished" version (0.5.x) and a different, redesigned, "beta" version, 0.9. Installing ALSA can be tricky and/or confusing. -

As of version 0.37 Pd works only with 0.9.x versions. +

As of version 0.37 Pd works only with 0.9.x versions. The RPM version of Pd is compiled for 0.9.x.

By default, Pd uses OSS. If you are running ALSA, Pd will use ALSA's OSS @@ -470,7 +414,7 @@ to be used, include the "-alsa" flag in the command line. flag. So, for instance, "-alsadev 3" means your third card, counting from one. You can also specify it the ALSA way: "-alsadev hw:3,0". -

Which sound card?

Here's a rundown on my experiences with sound cards so far. See @@ -483,24 +427,17 @@ I/O ports and one SPDIF. There is a "baby hammerfall" also, which I think is the "9632." DO NOT CONFUSE THE 9652/9632 WITH OTHER RME BOARDS WHICH MIGHT NOT WORK WITH PD. -

Guenter Geiger has an OSS driver for Hammerfall for 2.4 kernels (such as -RedHat 7.1 and up). You have to download and compile it: - - - http://gige.xdv.org/pages/rme . - -

You must then run Pd using the "-32bit' flag, because this uses a -non-standard extension of OSS to 32 bit samples. - -

Hammerfalls now have an ALSA driver; from what I hear -it won't work yet with Pd. I was unable to install the ALSA driver on the -two machines I tried ("no such device"). +

Hammerfalls now have an ALSA driver; aapparently, it works well to install +this and then run Pd using OSS emulation. (Unfortunately, this will only give +you 16 bit resolution. Maybe the also "plug" device will work better; I +haven't tried this.)

MIDIMAN

-Midiman sells devices with between 4 and 12 analog channels in and out, for -which there are ALSA drivers. It seems to work fine with the old ALSA driver -(0.5). I'm running mine in Alsa 0.9 beta 10. The driver name is "ice1712". +

Midiman sells PCI devices (delta 44, 66, 1010, and 1010LT) +with between 4 and 10 channels in and out, for +which there are ALSA drivers. +I'm running mine in Alsa 0.9 beta 10. The driver name is "ice1712".

Alsa provides an "envy24control" program (in "utils". You should run this and check that your ice1712's sync source is internal if you have no @@ -509,33 +446,35 @@ but don't take it for granted...

i810/i815

-In RedHat 7.0, motherboards with native i810 audio systems don't work in +

In RedHat 7.0, motherboards with native i810 audio systems don't work in full duplex (they crash linux). Either run Pd -noadc or else (better) install ALSA. -

3.4. Macintosh OSX

3.3. Installing Pd in Macintosh OSX

-Pd version 0.35 and up support Macintosh OSX, although there are still some -problems. You can always just download -the sources and compile it yourself, or (easier) +

Pd version 0.35 and up support Macintosh OSX, although there are still some +problems. You can always just download +the sources and compile them yourself, or (easier) find a MacOSX-style "package". The first package was put together by Adam -Lindsay and can be found on - -http://homepage.mac.com/atl/sw. The package simply installs itself -and you needn't follow the directions below. - -

To install on OSX from source:

+Lindsay and can be found on + +http://homepage.mac.com/atl/sw. The package simply installs itself +and you needn't follow the directions below. +

To install on OSX from source:

-Whether you've downloaded the source or the "package" you can -always compile Pd for yourself, whether to make your own improvements, or +

+Whether you've downloaded the source or the "package" you can +always compile Pd for yourself, whether to make your own improvements, or possibly so that you can get the newest version before it shows up compiled for -Mac OS X. +Mac OS X.

To be able to compile Pd, you must have installed Tcl/Tk -specifically in -/Applications/Wish Shell.app -and /Library/Frameworks/Tk.framework and /Library/Frameworks/Tcl.framework. +specifically in +/Applications/Wish Shell.app +and /Library/Frameworks/Tk.framework and /Library/Frameworks/Tcl.framework. +

First download and install TK for OSX (http://sourceforge.net/projects/tcl/). Get a recent one compiled for OSX, by chasing through "latest file releases", and finding a "download" @@ -547,9 +486,13 @@ on your system.

For old versions of Tcl/Tk you also had to get the "h" files from XFree86 and put them in /usr/X11R6/include. You can download just the H files from: -

-    http://www.crca.ucsd.edu/~msp/x.tgz
-

+ +

++http://www.crca.ucsd.edu/~msp/x.tgz + + +

(the individual files seem to have adequate copyright notices so that I can just redistribute them.) ((I hope this is no longer necessary but I notice people keep downloading these files anyway, so I'll leave them there @@ -559,19 +502,19 @@ a while longer until I'm sure they're not needed.)) such as ~/pd-0.35-test17 , cd to pd-0.36-0/src, type "./configure" and "make". Then type ~/pd-0.36-0/bin/pd to a shell and enjoy! -

If you wish you can put the line, +

If you wish you can put a line such as,

     alias pd ~/pd/bin/pd

-in the file, ~/.tcshrc, so that you can later just type "pd" to a shell. (The +

in the file, ~/.tcshrc, so that you can later just type "pd" to a shell. (The shell only reads the ~/.tcshrc file on startup, so this won't take effect in any existing shells unless you specially type

     source ~/.tcshrc

-to them.) +

to them.)

In some cases you have to explicitly give "-soundindev" and "-soundoutdev" flags for Pd to open audio correctly; "pd -listdev" should show you the @@ -587,9 +530,113 @@ I think you just download the OSX driver and follow directions. pd -midiindev 1 -midioutdev 2 -to get MIDI working. +

to get MIDI working. + +

3.4. Installing Pd in IRIX (SGI machines)

+ +

(NOTE: as of release 0.35 I haven't had an IRIX machine to compile +Pd on. Soeren Bovbjerg has kindly compiled 0.35 and 0.36 for IRIX; +you can find these at + http://www.cvmt.dk/~sb/ .) + +

Download Pd, which will be a "tar.Z" file. You can unpack this by +typing "zcat [name].tar.Z | tar xf -" to a shell. This creates a directory +named "pd". + +

+Starting with release 0.25, Pd should come in "n32" and "o32" versions. +"o32" is the default and will run on IRIX 5.x and up. "n32" runs faster, +but only on 6.x and up. Also, "externs" have to be updated for n32. The +"pd" executable (bin/pd in the distribution) is a symbolic link to either +"pd-o32" or "pd-n32." + +

NOTE: "externs" appear to be broken in the N32 version... I'm not sure +how long this has been true. If you want to use external objects, you have +to use the O32 version. + +

+If for example you put Pd in ~, the executable program +will be ~/pd/bin/pd. The program looks at its command line to +figure out where it is, so it's best to invoke Pd by its full pathname. +You should always invoke Pd from a Unix shell because many important +messages appear on the standard error. + +

+The simplest way to invoke Pd is to +make an alias in your ".cshrc" file (assuming you use the "c" shell) such as: +

+
+    alias pd ~/pd/bin/pd
+
+

(assuming your Pd distribution landed in ~, for example). + +

+Pd will open the "default" audio input and output devices, without regard +for whether they are in sync or not. This will be bad if they aren't; use +the "-noadc" or "-nodac" flag to disable either the input or output. Pd is +supposed to handle up to 8 channels of audio in and/or out. (But at least +one user had to recompile Pd on his Onyx to get 8 channels working.) + +

+As to MIDI, Pd simply attempts to open all available MIDI devices for input and +output, which is probably very bad on anything more recent than my Indy. If +any MIDI ports fail to open either for input or output, all MIDI is disabled. -

3.5. graphics rendering using GEM

Pd has not been fixed to request real-time priority from Irix; it will +compete with all other processes on your machine for CPU time. + +

Audio and MIDI in IRIX

+ +

+Pd takes command line arguments to set the number of input and output channels +and the sample rate. These don't affect the SGI's audio settings, which you +have to set separately using the "audio panel." Pd does detect the audio +sample rate if you don't specify one on the command line. + +

+On SGI machines, you have to work to get MIDI running. Before you start Pd, verify +that least one MIDI port is configured open. Pd opens the FIRST MIDI port +that's open. You might want to get rid of the "software" MIDI port if you're +running 6.x. On Indys, the usual practice is to open serial port number 2 +because some systems configure port 1 as "console" by default. You can use the +GUI if you want, or else just type +

+
+    startmidi -d /dev/ttyd2
+
+

+ +

to get port 2 speaking MIDI, and + +

+
+    stopmidi
+
+

+ +

to stop it. You can test whether MIDI is configured by typing, + +

+
+    ps -dafe | grep midi
+
+

+ +

and looking for "startmidi" processes. + +

+It's a good idea to connect your serial port to your MIDI interface before +typing the "startmidi" command, not afterward, at least in 5.x. We use the +Opcode Studio 3 interface but in principle any Mac-compatible one should work. + +

+The O2 apparently has RS232 ports, not RS422. I think SGI's web site says +something about how to deal with this. + + +

3.5. graphics rendering using GEM

GEM, originally by Mark Danks but now supported by Iohannes Zmoelnig, is essentially an extension of Pd that allows you to do OpenGL programming @@ -598,9 +645,9 @@ into Pd for audio. Find out more from Johannes's page. -

3.6. The Pd command line

-Pd is a "command line" program. The best way to run it is from your +

Pd is a "command line" program. The best way to run it is from your "terminal emulator," "shell," or "MSDOS prompt." The command line is:

@@ -609,33 +656,40 @@ Pd is a "command line" program.  The best way to run it is from your

-although you may have to specify a path so your command interpreter can find -Pd (OS dependent.) Possible options include: +

although you may have to specify a path (such as "~/pd/bin/pd" or +"C:\program files\pd\bin\pd") so your command interpreter can find +Pd. Possible options include:

 
 audio configuration flags:
--r            -- specify sample rate
+-r <n>           -- specify sample rate
+-audioindev ...  -- sound in device list; e.g., "2,1" for second and first
+-audiooutdev ... -- sound out device list, same as above 
+-audiodev ...    -- specify both -audioindev and -audiooutdev together
 -inchannels ...  -- number of audio in channels (by device, like "2" or "16,8")
 -outchannels ... -- number of audio out channels (by device)
 -channels ...    -- specify both input and output channels
--audiobuf     -- specify size of audio buffer in msec
--blocksize    -- specify audio I/O block size in sample frames
--sleepgrain   -- specify number of milliseconds to sleep when idle
+-audiobuf <n>    -- specify size of audio I/O buffer in msec
+-blocksize <n>   -- specify audio I/O block size in sample frames
+-sleepgrain <n>  -- specify number of milliseconds to sleep when idle
 -nodac           -- suppress audio output
 -noadc           -- suppress audio input
 -noaudio         -- suppress audio input and output (-nosound is synonym) 
--listdev          -- list audio and MIDI devices
--audioindev ...  -- sound in device list; e.g., "2,1" for second and first
--audiooutdev ... -- sound out device list, same as above 
--audiodev ...    -- specify both -audioindev and -audiooutdev together
+-listdev         -- list audio and MIDI devices
 
 (linux specific audio:)
--frags        -- specify number of audio fragments (defeats audiobuf)
--fragsize     -- specify log of fragment size ('blocksize' is better...)
--stream          -- use stream mode audio (e.g., for es1370 audio cards)
--alsa            -- use ALSA audio drivers
--alsadev      -- ALSA device # (counting from 1) or name: default hw:0,0
+-frags <n>       -- specify number of audio fragments (defeats audiobuf)
+-fragsize <n>    -- specify log of fragment size ('blocksize' is better...)
+-oss            -- use ALSA audio drivers
+-alsa           -- use ALSA audio drivers
+-pa             -- use portaudio (experimental version 19)
+-alsadev <n>     ----- obsolete: use -audiodev
+-32bit             ---- (probably obsolete) -- use 32 bit OSS extension
+
+(Windows specific audio:)
+-mmio           -- use MMIO drivers and API
+-asio           -- use ASIO drivers and API
 
 MIDI configuration flags:
 -midiindev ...   -- midi in device list; e.g., "1,3" for first and third
@@ -646,85 +700,73 @@ MIDI configuration flags:
 -nomidi          -- suppress MIDI input and output
 
 general flags:
--path      -- add to file search path
--open      -- open file(s) on startup
--lib       -- load object library(s)
--font         -- specify default font size in points
+-path <path>     -- add to file search path
+-helppath <path> -- add to help search path
+-open <file>     -- open file(s) on startup
+-lib <file>      -- load object library(s)
+-font <n>        -- specify default font size in points
 -verbose         -- extra printout on startup and when searching for files
--d            -- specify debug level
+-version         -- don't run Pd; just print out which version it is
+-d <n>           -- specify debug level
 -noloadbang      -- suppress all loadbangs
 -nogui           -- suppress starting the GUI
 -guicmd "cmd..." -- substitute another GUI program (e.g., rsh)
 -send "msg..."   -- send a message at startup (after patches are loaded)
 -rt or -realtime -- use real-time priority (needs root privilege)
 
--frags        -- specify number of audio fragments (defeats audiobuf)
--fragsize     -- specify log of fragment size ('blocksize' is better...)
--blocksize    -- specify audio I/O block size in sample frames
--stream          -- use stream mode audio (e.g., for es1370 audio cards)
--alsa            -- use ALSA audio drivers
--alsadev      -- ALSA device # (counting from 1) or name: default hw:0,0
+

-(MS Windows specific audio:) --resync -- resynchronize audio (default if more than 2 channels) --noresync -- never resynchronize audio I/O (default for stereo) --asio -- use ASIO audio driver (and not the 'MMIO' default) +

Here are some details on some of the audio, MIDI, and scheduler options (but +see also the next section on file management.) -MIDI configuration flags: --midiindev ... -- midi in device list; e.g., "1,3" for first and third --midioutdev ... -- midi out device list, same format --nomidiin -- suppress MIDI input --nomidiout -- suppress MIDI output --nomidi -- suppress MIDI input and output +

multiple devices.

-general flags: --path -- add to file search path --open -- open file(s) on startup --lib -- load object library(s) --font -- specify default font size in points --verbose -- extra printout on startup and when searching for files --d -- specify debug level --noloadbang -- suppress all loadbangs --nogui -- suppress starting the GUI --guicmd "cmd..." -- substitute another GUI program (e.g., rsh) --send "msg..." -- send a message at startup (after patches are loaded) --rt or -realtime -- use real-time priority (needs root privilege) - - +

You can specify multiple MIDI input and output devices. For example, +"pd -midiindev 3 -midioutdev 4,2" asks for the third MIDI input device and the +fourth and second MIDI output device. -Here are some details on some of the audio and MIDI options (but see also the -next section on file management.) +

Audio device selection is similar, except that you can also specify +channels by device: "-audioindev 1,3 -inchannels 2,8" will try to open device 1 +(2 channels) and device 3 (8 channels.) -

sample rate

sample rate.

-The sample rate controls Pd's logical sample rate which need not be that of +

The sample rate controls Pd's logical sample rate which need not be that of the audio input and output devices. If Pd's sample rate is wrong, time will flow at the wrong rate and synthetic sounds will be transposed. If the output and input devices are running at different rates, Pd will constantly drop frames to re-sync them, which will sound bad. You can disable input or output if this is a problem. -

audio buffer size

audio buffer size, block size, and sleep grain.

-You can specify an audio buffer size in milliseconds, typically between 10 and +

You can specify an audio buffer size in milliseconds, typically between 10 and 300, depending on how responsive your OS and drivers are. If this is set too low there will be audio I/O errors ("data late"). The higher the value is, on the other hand, the more throughput delay you will hear from the audio and/or control inputs (MIDI, GUI) and the audio coming out. -

In Linux and Windows, you can also specify the audio block size in sample -frames (but in Windows, this is only effective when using ASIO). +

You can also specify the audio block size in sample +frames. This is 64 by default (except for MMIO for which it's 256), and may +be 64, 128, or 256. -

MIDI devices

You can specify multiple MIDI input and output devices. For example, -"pd -midiindev 3 -midioutdev 4,2" asks for the third MIDI input device and the -fourth and second MIDI output device. The "channel message" midi objects in Pd +

The "sleepgrain" controls how long (in milliseconds) Pd sleeps between +periods of computation. This is normally the audio buffer divided by 4, but +no less than 0.1 and no more than 5. On most OSes, ingoing and outgoing MIDI +is quantized to this value, so if you care about MIDI timing, reduce this to 1. + +

MIDI

+ + The "channel message" midi objects in Pd such as notein or pgmout will take channels 1-16 to mean the first open MIDI port, 17-32 the second one, and so on. The midiin, sysexin, midiout objects give you a separate inlet to specify which of the open MIDI port numbers you want. +

System exclusive MIDI message inupt and output is theoretically supported +in version 0.37 but has not been tested. +

In Linux, if you ask for "pd -midioutdev 1" for instance, you get /dev/midi0 or /dev/midi00 (or even /dev/midi). "-midioutdev 45" would be /dev/midi44. In NT, device @@ -732,26 +774,45 @@ number 0 is the "MIDI mapper", which is the default MIDI device you selected from the control panel; counting from one, the device numbers are card numbers as listed by "pd -listdev." -

3.7. dealing with files

-Pd has a search path feature; you specify the path on the command line +

Pd has a search path feature; you specify the path on the command line using the "-path" option. Paths may contain any number of files. If you specify several files in a single "-path" option they're separated by colons -in unix or semicolons in NT. When Pd searches for an abstraction or an +in unix or semicolons in NT. + +

You can see and edit the path while Pd is running using the "path..." +item in the "File" menu. The path must be correctly set before you load +a patch or it may fail to find abstractions, etc., that are needed to +construct the patch. + +

When Pd searches for an abstraction or an "extern" it uses the path to try to find the necessary file. The "read" messages to qlists and arrays (aka tables) work the same way. NO SPACES MAY APPEAR ANYWHERE IN THE SEARCH PATH, e.g., "c:\my nonsense\goobers" won't work. +

Path entries may be relative to the patch directory; for instance, +if your path has an item, "../sound", and your patch is in "my stuff/all mine", +then Pd will look in "my stuff/sound". Spaces should be OK in the path to +the patch, but not in the path entry (../sound) itself. This is useful if +you have a patch and supporting files (even a supporting snapshot of pd) +that you want to distribute or carry around together. + +

Regardless of path, Pd should look first in the directory containing +the patch before searching down the path. (However, sometimes, for +reasons I can't explain yet, you have to put the entry "." in the +search path for this to happen, as least within linux!) +

Filenames in Pd are always separated by (unix-style) forward slashes, even if you're on Windows (which uses backslashes). This is so that patches can be ported more easily between operating systems. On the other hand, if you specify a filename on the command line (as in "pd -path c:\pdlib") the file separator should agree with the operating system.
-

If a filename in a patch has any "/" characters in it, the "path" is not -used; thus, "../sounds/sample1.wav" causes Pd only to look relative to the -directory containing the patch. (You may also invoke externs that way.) +

If a filename specified in a patch has any "/" characters in it, the "path" +is not used; thus, "../sounds/sample1.wav" causes Pd only to look relative to +the directory containing the patch. (You may also invoke externs that way.)

As of version 0.35, there may be spaces in the path to Pd itself; also, the "openpanel" and "savepanel" objects can handle spaces. But still not -- cgit v1.2.1