Search found 63 matches
- Thu May 21, 2009 11:29 am
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Re: USB MIDI Interface
Hi Dave, I've tested the timing with a program fragment like Patrick's (some posts above ^^). I checked the usb lines and the debug port pins with a scope. Pin D.7 toggles permanently with some inactivity (about 120µs) every 2 ms. So there's more than 90% of cpu activity for user program. Ciao Martin
- Thu May 14, 2009 10:06 am
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Re: USB MIDI Interface
Hi Dave,
could you please test my recommendation:to verify that it works well on win7.
Ciao Martin
Any Mac users around
could you please test my recommendation:
Code: Select all
bmAttributes=3 (interrupt), bIntervall=2
Ciao Martin
Any Mac users around
- Tue Apr 28, 2009 3:20 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Re: USB MIDI Interface
Hi, did some "research": linux: bmAttributes=2 (bulk), bIntervall don't care -> 2ms poll, low cpu load bmAttributes=3 (interrupt), bIntervall=1..3 -> 2ms poll, low cpu load bmAttributes=3 (interrupt), bIntervall=4..7 -> 4ms poll, low cpu load bmAttributes=3 (interrupt), bIntervall=8..15 ->...
- Tue Apr 28, 2009 9:56 am
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Re: USB MIDI Interface
... There's something i am wondering: Consumes 90% or more of the AVR's CPU time because bulk endpoints are polled aggressively by the host. Real-time applications on the AVR are close to impossible. Since we are now using bulk endpoint (are we?) is this a concern for us? ... Patrick Hi Patrick, I ...
- Thu Apr 23, 2009 11:21 am
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
USB MIDI Interface in Bulk mode 2 ms
Hi Patrick, I've read the descriptor section in main.c again and changed some values and suddenly -tada! - my test program sends data (4 or 8 byte) every two milliseconds! Then I started again step by step - it's only necessary to change the values of bmAttributes from 3 to 2 (Interrupt -> Bulk) in ...
- Wed Apr 22, 2009 10:37 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
USB MIDI Interface updated
Hi, I've just uploaded a new version of my project - it's got a new name V-USB-MIDI according to the new driver name. I made no big changes but I updated to the last version of v-usb (2009-04-15). V-USB-MIDI-0.2 hi pat, I have no idea how to speed up the communication - but maybe christian knows?? C...
- Mon Mar 23, 2009 10:55 am
- Forum: V-USB
- Topic: 12 mhz vs 20 mhz
- Replies: 2
- Views: 3306
- Mon Feb 23, 2009 10:31 am
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Hi hs4pmh, I didn't implement midi out but pat did it - look about 5 postings ^above^. He used a piece of code from m Concerning multi midi the doc midi10.pdf (p.13) says: USB-MIDI converters can connect to multiple Embedded MIDI Jacks. Each MIDI Endpoint in a USB-MIDI converter can be connected to ...
- Fri Feb 20, 2009 10:44 am
- Forum: V-USB
- Topic: avrusb and sleeping
- Replies: 2
- Views: 3286
- Mon Feb 09, 2009 11:44 am
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Hi Patrick, just returned from holidays - now I'm trying to dig into my code. I didn't use usbFunctionRead and usbFunctionWrite - if I understand correctly you can transfer some kind of config data in bigger chunks up to 254 bytes. These threads describe the programming: m m or look at the descripti...
- Wed Jan 21, 2009 9:10 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
- Fri Oct 31, 2008 4:55 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Hi Nuno, after some problems viewing your pics I found them - nice pice of hardware. How do you connect the 28 pots to the AVR - do you use a mux? That's what my project is intended for - letting musicians create their own midi gadgets. Do you know the pepper project? m This guy uses AVR-MIDI for dr...
- Fri Oct 10, 2008 4:38 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Hi, me again I've digged in the foum and found this thread: m about bulk/interrupt and timing. Funny, usb interrupt is not really interrupt. For my understanding interrupt has something to do with a door bell rung by a visitor and the usb spec behaves like someone who opens the door every minute to ...
- Thu Oct 09, 2008 6:32 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
Hi meh, the slow transfer rate comes from the usb standard. A low-speed device has no bulk transfer - it uses interrupt transfer at a rate of maximal 1000 messages/s. The midi protocol puts 1 or 2 midi commands (4 byte) into one message (8 byte) -> voilà! I hacked this project and it worked for my n...
- Tue May 20, 2008 10:38 pm
- Forum: V-USB
- Topic: USB MIDI Interface
- Replies: 93
- Views: 457876
V-USB-MIDI is online
Hi,
the first documentation and software is available at http://cryptomys.de/horo/V-USB-MIDI
Ciao Martin
EDIT 2009-04-23: new name and new URL
EDIT 2016-02-15: new name also in header
the first documentation and software is available at http://cryptomys.de/horo/V-USB-MIDI
Ciao Martin
EDIT 2009-04-23: new name and new URL
EDIT 2016-02-15: new name also in header