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Your finished subVI should behave like this one:

Coding tips

Watch the screencast video to learn how to assemble a byte at the bit level, and also how to set up the enumerated data type for a case structure.

[video] Learn how to assemble a byte at the bit level, and learn how to set up an enumerated data type for a case structure

Midi_makedtmetaevent.vi

midi_MakeDtMeta.vi creates a delta-time / meta-event pair. The subVI accepts a delta-time in ticks, a meta-event selector, text string, and tempo value (only certain meta-events require the last two inputs). The delta-time is converted into variable-length format, and the meta-event is created. Both of these values are appended to the inbound string to produce the output string. Review the module Standard MIDI Files to learn about meta-events.

Input requirements

  • string in (string type)
  • delta time (32-bit unsigned integer; defaults to 0)
  • event (enumerated data type with values Text, Copyright Notice Text, Track Name, Instrument Name, Lyric Text, Marker Text, Cue Point Text, Sequencer-Specific, End of Track, and Set Tempo; defaults to Track Name)
  • text (string type)
  • tempo (32-bit unsigned integer; defaults to 500,000)

Output requirements

  • string out (string type)

Behavior requirements

  • Convert the delta time value to VLF format using the midi_ToVLF.vi subVI you created in a previous step
  • Create a meta-event sub-string using the sequence 0xFF (indicates meta-event), meta-event type (refer to a table of meta-event type numbers), meta-event length (use midi_ToVLF.vi for this purpose), and meta-event data.
  • Append the delta-time sub-string and the MIDI message sub-string to the inbound string, and output the result

Your finished subVI should behave like this one:

Coding tips

At this point you should have enough experience to proceed without assistance!

Top-level vi application

Congratulations! You now have assembled and tested six subVIs that can form the basis of many other projects. Now use your subVIs to build an application VI (top-level VI) to demonstrate that your subVIs work properly together. Two applications that you can easily build are described next.

Sweep through notes and tones

The application block diagram pictured below produces a single-track MIDI file containing an ascending chromatic sweep over the entire range of note numbers (0 to 127). Before sounding the note, the Program Number (tone or voice selection) is set to the same value as the note number. Thus, the voice changes for each note, adding additional interest to the sound. The note duration is specified by a control whose unit is milliseconds. As an exercise, you will need to complete the grayed-out area to convert the units of“duration”from milliseconds to ticks.

Block diagram to produce a single-track MIDI file containing an ascending chromatic sweep over the entire range of note numbers (0 to 127)

Measure the velocity profile of your soundcard

The application block diagram pictured below creates a MIDI file in which the same note is played repeatedly, but the velocity varies from the maximum to the minimum value in unit steps. When you play the MIDI file, you can record the soundcard’s audio output and measure its velocity profile , i.e., the mapping between the note’s velocity value and its waveform amplitude. The Audacity sound editing application works well for this purpose; choose“Wave Out Mix”as the input device to record the soundcard’s output.

Block diagram to play a single note with velocity varied from 127 down to 0

Questions & Answers

Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
Virgil
is Bucky paper clear?
CYNTHIA
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
NANO
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
tahir
On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
what is biological synthesis of nanoparticles
Sanket Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, Musical signal processing with labview -- midi for synthesis and algorithm control. OpenStax CNX. Nov 09, 2007 Download for free at http://cnx.org/content/col10487/1.2
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