fuzzy1969
100+ Head-Fier
- Joined
- Nov 7, 2010
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Apex Glacier is confirmed for the s3
The Host(in your case the S3) is using the Vbus line(a.k.a. red wire or pin 1 or Vcc or +5v) to send some current/voltage to communicate and I'm not really sure how your test cable works but if you mean the "switchable 5v" is actually cutting off the connection of the Vbus line than you're test is flawed since if disconnected the Vbus line then would not be able to send or receive signal/info/voltage and communication is lost between them therefore no chance of ever the external DAC taking over the S3 DAC.
I'm not too sure how you would test this but if you can monitor the correct voltages/current of the Vbus line to see if it's always on or actually just pulsing(on and off) for some period of time and then maybe turns off altogether then maybe you could tell if it's powering a device or just communicating with it.
the O2/ODAC combo doesn't have batteries so its no go for portable use for sure.
Uhm, yeah... Thanks for pointing out my half-assed post...
I was working on something else, and as a true ADDer is supposed to, got distracted by this and ended up posting less than complete info (and botched up the CAD drawing for my 'listening chair'-project in the process too)...
Hahaha...that's the fun of it I guess.
The 'switching' my quick & dirty test setup did, was not of the actual 5V, but wether a 64.9KΩ resistor was in the connection between sense and ground on the OTG cable to trick the phone into thinking an audio dock was connected instead of a regular OTG cable. Audio dock mode allows the S3 to charge while still allowing for OTG functionality. I am/was under the impression that this would disable any 'outgoing power' from the phones USB connector. Please educate me if I misunderstood
Ah I see....it's the "fun with resistors thingy" to invoke the differing modes available on Samsung android phones though I'm not too sure exactly how all that works.
If you could point me to some docs that I can read that would be good. I'm here to learn too.
With the phone in audio dock mode, the DAC wouldn't work without an external power source, even though the internal battery of the D2+ was between 90 and 100% charge. Hence my conclusion that the D2+ has no 'self-powered mode'. Feel free to point out any flaws in my ADD-infused logic, I'm here to learn
You are actually contradicting yourself with the statement above since my understanding of a self powered device is exactly that it would not work without an external power source.The DAC would work if it's bus powered and taking power from the host.So that is the reason why I think your test is flawed as it neither proves nor disprove whether
the DAC is self powered or bus powered or has both.
Unfortunately, I can't really take any useful measurements right now. My multimeter died some time ago, together with my soldering station (don't ask, long story), and I can't afford to replace it at the moment (replacement soldering station has priority), I'm using a €2,95 china special for the time being. Which is good enough for measuring constant values, but simply isn't quick enough to measure a pulse (and with this multimeter, a pulse is anything taking less than 5 seconds).
I'll gladly retest with any additional information you provide and a better multimeter as soon as I have it (any suggestions for a very cheap multimeter with PC, preferably USB, interface are welcome too).
I'm not really an authority in this so you might want to find info elsewhere.Anyway I'm really not too concern whether a DAC is self-powered or bus-powered as like I said I'm using my S3 with the extended battery that can last me the whole day with music listening and heavy usage and is enough for all my needs, and as far as I know max a device will
draw is 500mA and usually will only draw 100mA of power.So like you said the battery on the S3 should not be effected too much but it will be a plus if the DAC is self powered but not a big deal if it wasn't.
Anyway it'll be nice to see you trying to come out with a valid test and try some DACs to see if it's self powered or bus powered.
Good Luck!!
Ah I see....it's the "fun with resistors thingy" to invoke the differing modes available on Samsung android phones though I'm not too sure exactly how all that works.
If you could point me to some docs that I can read that would be good. I'm here to learn too.
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You are actually contradicting yourself with the statement above since my understanding of a self powered device is exactly that it would not work without an external power source.The DAC would work if it's bus powered and taking power from the host.So that is the reason why I think your test is flawed as it neither proves nor disprove whether
the DAC is self powered or bus powered or has both.
Anyway, here's a list of resistor values I found somewhere on a (this?) forum:
ADC_DOCK_VOL_DN = 0x0a, /* 0x01010 14.46K ohm */
ADC_DOCK_VOL_UP = 0x0b, /* 0x01011 17.26K ohm */
ADC_DOCK_PLAY_PAUSE_KEY = 0x0d,
ADC_SMARTDOCK = 0x10, /* 0x10000 40.2K ohm */
ADC_AUDIODOCK = 0x12, /* 0x10010 64.9K ohm */
ADC_CEA936ATYPE1_CHG = 0x17, /* 0x10111 200K ohm */
ADC_JIG_USB_OFF = 0x18, /* 0x11000 255K ohm */
ADC_JIG_USB_ON = 0x19, /* 0x11001 301K ohm */
ADC_DESKDOCK = 0x1a, /* 0x11010 365K ohm */
ADC_CEA936ATYPE2_CHG = 0x1b, /* 0x11011 442K ohm */
ADC_JIG_UART_OFF = 0x1c, /* 0x11100 523K ohm */
ADC_JIG_UART_ON = 0x1d, /* 0x11101 619K ohm */
ADC_CARDOCK = 0x1d, /* 0x11101 619K ohm */
#if defined(CONFIG_MUIC_DET_JACK)
ADC_EARJACK = 0x1e, /* 0x11110 1000 or 1002 ohm */
Noob here, I just recently started using my Motorloa XYboard to play FLAC files in my car via the 3.5mm to the IP bus on my source. I've been searching but cant find a solid answer to weather the internal DAC can be bypassed through either micro USB or mini HDMI. I also have a Droid DNA I could use too, but I prefer the tablet. Thanks