01.04.11

iPhone integration with audio kit – the solution

Posted in Home at 12:01 pm by admin

A little while ago I set out on a quest to be able to insert my iPhone into my audio setup to allow me to use the studio as a hends free interface for calls. It’s seems very frivilus now that I read that back, but it’s actually important to be able to caprute the calls to.. so there!

Anyway, time moved on and I had some little success building various cables and experimenting but my solution came in the form of a relatively simple little device designed to do something totally different (isn’t that always the way), namely to provide an interface to connect an electric guitar to the iPhone (or iPod Touch or iPad). The manufacturer is Peavey – those of you in the know will already have the association made as Peavey are well know for their guitar amplifiers among other things – and the device is the Ampkit Link.

This innocuous little white widget does exactly what I want it to do and I’m now a very happy, and very audio integrated, person. The XBox side of the equation is going to be handled by a simple adaptor cable which I’ll build up as the connections are different on the iPone jack – and therefore on the Peavey device – than on the XBox controller.

As an aside, the app which supports the Link hardware is free for a basic version and, if you’re a guitar person with an i-Device, might be worth a look-see.

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11.09.10

Am I backing the wrong horse?

Posted in Work at 8:44 pm by admin

There’s something which has been eating at me for a while now, it’s been there scratching away at the back of my mind like some gnawing bug but today it crystallised.

The event was an article in a news feed I get from SearchStorage. The article itself is an interesting piece on how NetApp are updating their mid-high end FAS arrays (OK it’s only interesting if you’re into storage subsystems!) but the key phrases which stood out were these:

“… and a FlexPod bundle that includes Cisco server and switching products and VMware server virtualization applications with the FAS3200″

“The FlexPod is an answer to EMC’s Vblock bundles that also include Cisco servers and switches and VMware software.”

Here we have NetApp, a key performer at Microsoft’s Hosting Summit this year with all of the talk about “Cloud services” lining up a competitor to vBlock using VMware – one of the foundations stones of vBlock!  The question I asked myself is this… Where the hell is Hyper-V?!

Over and over, I’m seeing cloud architectures and solution using VMware, the partners which Microsoft themselves have been sharing media time with have VMware solutions as their center-fold products in this space.And even where there IS a Microsoft program for the hardware vendors to tie in to, it’s a very interesting bit of reading when you do follow the vendor links placed there. Of all of the big names, I found 1 (one!) who had dedicated information for me to access related to the architectures the program refers too. All of the others followed the standard approach of ‘As part of the delivery of this program we’ll be using these great products which we sell <link><link><link>. There were no pre-validated configurations available which I could measure my requirements against!

I’m going to link HERE to the only decent landing page there was, it’s DELL. They had a single page, with some interesting and usable reference documentation at the bottom. Documentation which seemed to have bee written specifically for this program.

So here’s my issue, I like Hyper-V, I like the Systems Centre elements supporting it (VMM Self Service Portal v2 is sweet!) I’ve deployed or been part of project deploying, quite a number of environment delivering large-scale services running on Hyper-V, BUT  VMware seems part of all of the ‘solutions’ which are coming forward. Am I backing the wrong horse??

Then I read this in RCPmag which, not for the first time, questioned what Microsoft actual strategy is in terms of ‘The Cloud” (I really do hope we can move away from that moniker soon!) and talks of the current moves simply being a ‘prevent’ rather than succeed plan. Whatever it is, it leave us, out here trying to build business cases and for strategies with our customers, scrabbling a little for something solid.

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09.15.10

iPhone hands-free using Line In-Out, or not.

Posted in Home at 12:09 pm by JohnB

So here’s the goal. I want to plug my iPhone into a dock and use my audio kit as a hands free kit for making and recieving calls. (In case you don’t know everything I have in the office which makes a noise or needs a microphone is routed through a set of mixers and processors and I can records from any source for podcasts etc etc. geeky but cool – if you’re me)

As you can see from the pinout below, the IPOD connector on the iPhone supports line-in and line out although you do need to put a specific value of resistor across a couple of lines to ‘switch’ this functionality on.

Pin	Signal	Description
1	GND	Ground (-), internally connected with Pin 2 on iPod motherboard
2	GND	Audio & Video ground (-), internally connected with Pin 1 on iPod motherboard
3	Right	Line Out – R (+) (Audio output, right channel)
4	Left	Line Out – L(+) (Audio output, left channel)
5	Right In	Line In – R (+)
6	Left In	Line In – L (+)
8	Video Out	Composite video output (only when slideshow active on iPod Photo)
9	S-Video Chrominance output	for iPod Color, Photo only
10	S-Video Luminance output	for iPod Color, Photo only
11	GND	If connected to GND the iPhone sends audio signals through pin 3-4, otherwise it uses onboard speaker.
12	Tx	ipod sending line, Serial TxD
13	Rx	ipod receiving line, Serial RxD
14	RSVD	Reserved
15	GND	Ground (-), internally connected with pin 16 on iPod motherboard
16	GND	USB GND (-), internally connected with pin 15 on iPod motherboard
17	RSVD	Reserved
18	3.3V	3.3V Power (+)  Stepped up to provide +5 VDC to USB on iPod Camera Connector. If iPod is put to sleep while Camera Connector is present, +5 VDC at this pin slowly drains back to 0 VDC.
19,20	+12V	Firewire Power 12 VDC (+)
21	Accessory Indicator/Serial enable	Different resistances indicate accessory type: 1kOhm – iPod docking station, beeps when connected 10kOhm – Takes some iPods into photo import mode 68kOhm – makes iPhone 3g send audio through line-out without any messages 500kOhm – related to serial communication / used to enable serial communications Used in Dension Ice Link Plus car interface 1MOhm – Belkin auto adaptor, iPod shuts down automatically when power disconnected Connecting pin 21 to ground with a 1MOhm resistor does stop the ipod when power (i.e. Firewire-12V) is cut. Looks to be that when this pin is grounded it closes a switch so that on loss of power the Ipod shuts off. Dock has the same Resistor.
22	TPA (-)	FireWire Data TPA (-)
23	5 VDC (+)	USB Power 5 VDC (+)
24	TPA (+)	FireWire Data TPA (+)
25	Data (-)	USB Data (-)
26	TPB (-)	FireWire Data TPB (-)
27	Data (+)	USB Data (+)  Pins 25 and 27 may be used in different manner. To force the iPod 5G to charge in any case, when USB Power 5 VDC (pin 23) is fed, 25 must be connected to 5V through a 10kOhm resistor, and 27 must be connected to the Ground (for example: pin 1) with a 10kOhm resistor. iPod 5G can also be forced to charge by attaching the data + and the data – pins to the 5v via a 10k Ohm resistor ( BOTH PINS) and connecting pin 16 to the 5v (ground). (Confirmed working with iPod 5G 20GB) To charge an iPhone 3G / iPod Touch 2nd gen or Ipod Classic (6th Gen), usb data- (25) should be at 2.8v, usb data+(27) should be at 2.0v. This can be done with a few simple resistors: 33k to +5v (23) and 22k to gnd(16) to obtain 2v and 33k to +5v and 47k to gnd to obtain 2.8v. This is a notification to the iphone that it is connected to the external charger and may drain amps from the usb. It’s also possible to charge the iPod’s or iPhone’s battery to make use the of internal +3.3v output (18) terminal to connect the USB Data + (27) thru a 47k ohms resistor and the USB Data- (25) thru a 47k resistor to the USB Power source +5v (23).  This way the USB function is still useable for normal operations and makes it easier the fit in a plug. The resistors are not to critical 2x 150k’s still work.
28	TPB (+)	FireWire Data TPB (+)
29,30	GND	FireWire Ground (-)

Back side of dock connector;
 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
 1 3 5 7 9 11 13 15 17 19 21 23 25 27 29

My simple brain therefore led me to believe that is should be a simple matter of using those lines and feeding them at the correct level from the in/out of my main mixer. HAH!

The Line-Out is indeed enabled BUT the audio from phone calls is not presented on that circuit. I'm sure that this is a software thing but for the life of me I can't understand why it wouldn't be enabled in this way unless it's a simple method of controlling the ability for 3rd parties to create hand's free kits. It's bluetooth or nowt!

I did get a universal dock of eBay and I am feeding the line out from it into my mixer just in case I ever need an additional audio source but I'm disappointed that I can't use it for calls. The only way I can achieve what I want is to use the top connector on the iPhone which is a TRRS connector however this is set up to support headphones and an electret mic so I'm going to have to mess around with capacitors and resistors again, BAH!

Tip - Left Audio

Ring - Rign Audio

Ring - Ground (I know!)

Shield - Mic in

I did find an interesting article by a guy who'd created a neat little box to use to record his calls, but this still relied on using 'standard' headphones and an electret mic so doesn't really help too much. Oh well, where's my soldering iron?!

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