Raspberry Pi

[The ghost of raids past]

Cancelled mine. It was supposed to be dispatched within 3 weeks, it wasnt and now to add insult to injury you have to wait up to 15 days for the refund to be made.

[MattyP]

What SD cards are you lot using?

I've changed may camera so need to order a card for that and I'll need one for my on order R-Pi.

Just used a standard el-cheapo one I picked up from Track because I didn't have a spare one laying about when it arrived. 4GB TDK class 4 unit cost £4.97. Works well enough. Obviously the main limitation will be the speed of transfer from the RPI too... not sure what that is off hand. Seems to work OK though. Not blindingly fast but good enough for messing about with!

[Firefox]

Hmmm, it turns out that mine only works with my new digital TV and my big-ass old TV that I've got my various retro consoles plugged into. It does not work with the monitors on my desk.

I suppose I should really have a go using it as it was intended - plugged into the living room telly - rather than as a target platform hooked up to my PC. I'll have to get it working with wifi somehow, though...

[MattyP]

What SD cards are you lot using?

I've changed may camera so need to order a card for that and I'll need one for my on order R-Pi.

Just used a standard el-cheapo one I picked up from Track because I didn't have a spare one laying about when it arrived. 4GB TDK class 4 unit cost £4.97. Works well enough. Obviously the main limitation will be the speed of transfer from the RPI too... not sure what that is off hand. Seems to work OK though. Not blindingly fast but good enough for messing about with!

Track = Tesco btw flippin' phone touch screens, word prediction software and virtual keyboards.... Grrrrrr

[zip accident]

Hmmm, it turns out that mine only works with my new digital TV and my big-ass old TV that I've got my various retro consoles plugged into. It does not work with the monitors on my desk.

What connectors are you using?

I tried my laptop on my main monitor once, through a HDMI to DVI converter it would only display the laptop's screen at the laptop's resolution, through VGA into the monitor's VGA socket it would show a lot more, including using them as separate screens. I'm not suggesting using VGA for the RasPI, but I am interested in exactly what didn't work and how much it didn't work, I gave the example of the VGA to show how much the HDMI wouldn't do comparatively.

[tufty]

How did you get vga?

[Firefox]

What connectors are you using?

HDMI to DVI cable.

Prob'ly my monitor's too old and doesn't implement... whatever spec they say you need on the Raspberry Pi wiki.

[zip accident]

How did you get vga?

I was seeing how my laptop connected. It had VGA out, I had a cable, the monitor has VGA in. It's not a PI, but I thought the HDMI part of the experience was relevant. It may be HDMI wouldn't have worked at all if the laptop hadn't had it's own display. I was left pretty unimpressed with HDMI as a way of getting a display out of a laptop.

Particularly, I would have liked to have seen a 1080p display on the monitor, which HDMI should be capable of, and the monitor being 1920 x 1200 is certainly capable of. I was using a DVI to HDMI connector reversed connected to an HDMI cable, maybe that was unacceptable to HDMI's DRM aspect, I don't know, but if that's what the problem was, I'm surprised I got output on the monitor at all.

What connectors are you using?

HDMI to DVI cable.

Prob'ly my monitor's too old and doesn't implement... whatever spec they say you need on the Raspberry Pi wiki.

Well, my monitor's not old (well, six months or less), possibly implementation is optional for DVI in?

[tufty]

How did you get vga?

I was seeing how my laptop connected. It had VGA out, I had a cable, the monitor has VGA in. It's not a PI, but I thought the HDMI part of the experience was relevant. It may be HDMI wouldn't have worked at all if the laptop hadn't had it's own display. I was left pretty unimpressed with HDMI as a way of getting a display out of a laptop.

Ah, right, misread you.

I suspect it's a misconfiguration or driver issue on your laptop, to be honest - having the display nailed to the resolution of the panel seems a lot like you're set up to "mirror" your internal display rather than treat HDMI as a separate display.

[Ratsoap]

Turns out there has been a Raspberry Pi IN MY HOUSE for nearly a month. My cousin is storing some stuff here.

'Oh that' he says, 'keep it, I have two'.

[Kelloggs]

Yay! I finally got one to play with! So, without further ado, have a MIDI split-point generator!

CODE

Spoiler: show

Code: Select all

!/usr/bin/perl -w

use 5.10.1;

until (-e "/dev/midi") {}                                       # Wait until it's plugged in...

open INPUT, "<:raw", "/dev/midi" or die "Can't open /dev/midi for input";
open OUTPUT, ">:raw", "/dev/midi" or die "Can't open /dev/midi for output";

print OUTPUT pack("CC",196,33);                                 # Set a GM Bass on channel 5

while(read(INPUT,$inp,1))                                       # Are we getting anything?
{
  $byte=unpack("C",$inp);                                       # Grab a byte

  given ($byte)
  {
    when ([128..155])                                           # Note-On or Note-Off, any channel
    {
      $cmnd=$byte & 0xf0; $chan=$byte & 0x0f;                     # Separate out the channel

      read(INPUT,$inp,2);
      ($pitch,$vel)=unpack("CC",$inp);

      if($pitch<=60)                                              # Middle C or below
      {
        $chan=4; $pitch-=12;                                      # Change the channel, drop the pitch
      }

      print OUTPUT pack("CCC",($cmnd|$chan),$pitch,$vel);         # And sling forth...
    }

    default
    {
      print OUTPUT pack("C",$byte);                             # Send everything else unaltered
    }
  }
}

I've got a Yamaha CS1x, which doesn't do (sensible, multi-channel) splits. What it does, however, is a rather nice Performance mode (channel 1 on mine, but takes up 2,3 and 4 as well) and the rest are GM instruments. So, we read a byte and if it's a note, we change its channel to 5 and drop it by an octave. Plug a USB-MIDI adaptor into both In and Out on the keyboard, and turn Local Control off, and away you go!

Technical notes: RasPi seems not to like booting up with USB->Midi adaptor plugged in, so the code waits until there's a /dev/midi available. Also, I'm not certain that the read/unpack and pack/print are the most elegant way of handling raw bytes in Perl. I was originally going to write it in Python, but the Python MIDI handling seems to be old and fossilised, so I just grabbed a spare language. I can do it in C without any problem, but the thing is fast enough as is, and this way it's edit-run instead of edit-compile-run. Needs a fairly modern Perl, though, which fortunately the RPi Debian comes with.

[Darkflame]

Could one of these be used to make a live visualizer? (somehow get mic audio input then output prettiness to the tv?)

Could be good fun.

[Kelloggs]

You'll need an audio input (only output on the board) but any old USB audio interface should do if Linux supports it, which will be most of them. If you've got one hanging round, plug it in and see what happens (but it'll probably need its own power supply - the Pi's USB data is fine, but there's reports that its USB power is a bit anaemic).

[matt303]

Got email saying mine has been dispatched 24hr delivery

[Misfit]

Got my code, but couldn't order for 24 hours (my workmate is getting it as Wanye gave me a code) and when I placed my order it told me to expect it in 11 weeks!

I see you can now order cases for under a fiver too.