CAN bus information - MTCD Hardware Development

Hello, wondering if any one could help me out. I'm trying to find out information on using a direct link between our radios and the can bus without using a can box... Does any one have any information if the two pins in the main connector labeled can+rx/can-tx at locations pin 1 and pin 11 in the attached picture, can be utilities for this. Thanks!

trav473 said:
Hello, wondering if any one could help me out. I'm trying to find out information on using a direct link between our radios and the can bus without using a can box... Does any one have any information if the two pins in the main connector labeled can+rx/can-tx at locations pin 1 and pin 11 in the attached picture, can be utilities for this. Thanks!
Click to expand...
Click to collapse
While I am certainly no expert here, I would say that you probably can not interface with the vehicle without something to interpret the data coming from the vehicle. Canbus, Arduino, R2-D2, etc.
Your quest needs more info. What is the ultimate goal?

From what i have seen, experienced on this so far is the CANBox job is two fold, one is electrical interface to car and the other is software , on the software side there are subtle difference between cars on OBD code meanings, these boxes convert the signals in both electrical format (12volts can differential to 3.3 can tx/rx) and software format so the signal coming out to the head unit is a common CAN protocol at low voltage for the headunit regardless if the car is using CAN, K Line, KKL type protocols.
see the schematics here https://forum.xda-developers.com/android-auto/mtcd-hardware-development/canbox-versions-t3763383
I'am currently reverse engineering one for a vw right now for purpose of research for fun.
darkspr1te

darkspr1te said:
From what i have seen, experienced on this so far is the CANBox job is two fold, one is electrical interface to car and the other is software , on the software side there are subtle difference between cars on OBD code meanings, these boxes convert the signals in both electrical format (12volts can differential to 3.3 can tx/rx) and software format so the signal coming out to the head unit is a common CAN protocol at low voltage for the headunit regardless if the car is using CAN, K Line, KKL type protocols.
see the schematics here https://forum.xda-developers.com/android-auto/mtcd-hardware-development/canbox-versions-t3763383
I'am currently reverse engineering one for a vw right now for purpose of research for fun.
darkspr1te
Click to expand...
Click to collapse
This is what I am somewhat looking for... I was figuring as much that the Can boxes were to make the connections to various OEMs universal between the Android radios. I'm researching for the heavy duty truck market. That market all uses a J1939 SAE standard and I'm wanting to see if it was possible to perform all the translation (hardware and software) within the MCU.... And do away with the CAN box.... Thanks for the info... I plan on building an Arduino box to start sorting out the data that is broadcast on that datelink, but need the know what the possible expectation the MCU is looking for on the input side...

trav473 said:
This is what I am somewhat looking for... I was figuring as much that the Can boxes were to make the connections to various OEMs universal between the Android radios. I'm researching for the heavy duty truck market. That market all uses a J1939 SAE standard and I'm wanting to see if it was possible to perform all the translation (hardware and software) within the MCU.... And do away with the CAN box.... Thanks for the info... I plan on building an Arduino box to start sorting out the data that is broadcast on that datelink, but need the know what the possible expectation the MCU is looking for on the input side...
Click to expand...
Click to collapse
I have made progress on this,
see
CANBOX reverse engineering

I think you can use an OBD2 ELM327 adapter selecting the correct protocol with command AT SP <n>. Search correct number <n> in ELM327 command list. That selection remains permanent in the device. This way you will have text messages formed with byte numbers in hexadecimal format. The USB/Serial speed will be apparently 38400 bps or perhaps another as 115200. But I think it is simply an USB connection and serial speed doesn't matter about response time. I have a device that only works fine at 38400 bps as it sends strange symbols at 115200, for example. It is possible to install OBD2 device hidden giving it supply through pin 16 and connecting pins 6 and 14 CANBUS. I wish to do this installation but my car has easy accesible CANBUS through a TTL line that arrives to the radio, almost sure in P2P mode, not two lines at 2.5 V with dominant and recessive states as a multinode bus.

I think OBD2 devices used to program ECUs works with pure binary messages (standard SAE J2534). But I don't know messages format nor protocol. Nevertheless, although in ASCII format programs have more work to do, they are easier to do.

Hello everyone and greetings from Greece!
I am a university student of Mechanical Engineering and I have to take on my diploma thesis at car CAN bus communications. My teacher has asked me to find information on this topic like: bibliography, articles etc. from official and valid sources and learn some basics. For exhample: what is CAN bus, Linbus, what the K communication line does etc. As well as to find a cheap CAN bus usb interface, software and a simple dbc file to do some very basic measurements (not encrypted) at a vehicle.
Any help is useful for me! Also if u have another forum at your mind that i can write please tell me.
Thank you very much in advance everyone for your time and for your help!

ok, I will tell you first that this is a big rabbit hole you are going down but I have some tips for you that will assist.
CAN bus refers to a specific communications type (protocol, voltage, topology) as does K-line, KKL , LIN bus, RS 485 etc , they often are pooled together under the names like OBDII/j2534/sae j1962 . then you will also see that the individual systems will also have other names like K-line is also known as ISO9194.
Then there are interface's you will see that are not in OBDII but 'maybe OBD1' like ALDL (a GM system often used in Suzuki vitara's up to 1996) or ford EEC III/IV up to 2000.
This will also mean that the plugs on the car for interfacing maybe different between brands so for practical work make sure you choose a recent car that falls under latest EU regs for OBD access.
If you choose your thesis on OBDII and it's sub protocols you might be out of luck as most of the good sites with technical info are on russian servers/DNS and i've found them off line recently.
If you choose a sub protocol (canbus for example) there a lot of info on EEVBlog forums, canbus wiki. There is also info on the Open ECU forums and openOBD forums if it's still up (great site for info but very toxic)
If you are going into the practical side more (bus sniffing, replay attacks etc) you will need OBD2 splitters, OBD2 reader "like the elm327" and a CANbus chip and MCU to put custom code on.
I chose stm32 based chips for the canbus MCU side and use both CANBUS inverters(electrical connection to canbus network) and mcp2515 spi canbus interface (converts canbus to spi)
also a good DSO wont go amiss if you dont have access to one at uni.
darkspr1te
some easy links
Canbus links

darkspr1te said:
ok, I will tell you first that this is a big rabbit hole you are going down but I have some tips for you that will assist.
CAN bus refers to a specific communications type (protocol, voltage, topology) as does K-line, KKL , LIN bus, RS 485 etc , they often are pooled together under the names like OBDII/j2534/sae j1962 . then you will also see that the individual systems will also have other names like K-line is also known as ISO9194.
Then there are interface's you will see that are not in OBDII but 'maybe OBD1' like ALDL (a GM system often used in Suzuki vitara's up to 1996) or ford EEC III/IV up to 2000.
This will also mean that the plugs on the car for interfacing maybe different between brands so for practical work make sure you choose a recent car that falls under latest EU regs for OBD access.
If you choose your thesis on OBDII and it's sub protocols you might be out of luck as most of the good sites with technical info are on russian servers/DNS and i've found them off line recently.
If you choose a sub protocol (canbus for example) there a lot of info on EEVBlog forums, canbus wiki. There is also info on the Open ECU forums and openOBD forums if it's still up (great site for info but very toxic)
If you are going into the practical side more (bus sniffing, replay attacks etc) you will need OBD2 splitters, OBD2 reader "like the elm327" and a CANbus chip and MCU to put custom code on.
I chose stm32 based chips for the canbus MCU side and use both CANBUS inverters(electrical connection to canbus network) and mcp2515 spi canbus interface (converts canbus to spi)
also a good DSO wont go amiss if you dont have access to one at uni.
darkspr1te
some easy links
Canbus links
Click to expand...
Click to collapse
Okay, thank you, I will take into account what you have mentioned. I believe the links will help me in the thesis. Greetings!

Related

GSM Positioning via cell sites

Hello all,
I have been reading the different boards and there was a very interesting discussion taking place in the "developers corner". Apparrently, they have found a way to put a call into the radio stack of the xda and have it return values which correspond to cell site position ( both the cell site identifiers and their approximate distance from it).
I was wondering if this means that we may find ourselves with an application that can give us positioning?
Thanks for your help.
Gene
Gene_uk said:
Hello all,
I have been reading the different boards and there was a very interesting discussion taking place in the "developers corner". Apparrently, they have found a way to put a call into the radio stack of the xda and have it return values which correspond to cell site position ( both the cell site identifiers and their approximate distance from it).
I was wondering if this means that we may find ourselves with an application that can give us positioning?
Thanks for your help.
Gene
Click to expand...
Click to collapse
Gene,
Yeah, I'm interested in that as well but having a few issues. A lot of the samples of getting the Cell ID are in C/C++, pre-compiled apps, or from the bootloader. Seeing as I'm not C savvy, I'm having a tough time trying to get it to work in eVB [Not that I have much time anyway at the moment].
I read ages ago, on the sourceo2 newsgroups, that O2 [UK] won't release the information on Cell locations. Well, they will but only subsets and only for a price. I then noticed that a mate of mine recently got a camera phone Nokia 7xxx or something. Anyway, he had this Java proggy that told him the ID of the Cell and Area he was in. It got me thinking of writing my own app for the XDA.
His proggy was pretty cool actually. It allows the user to set up events depending on when you are entering or leaving a cell. One use of it, is to automatically switch the phone to silent when entering the area of a cinema. Or as he put it, welcoming you home, when you get to a cell near your house. The mad thing
Basically I was thinking or writing an App initially with two functions. The first would be that it can recognise the Cell ID and allow you to input the general location of where you are. As the Cell ID changes, the app would prompt for a new location description.
The second function would be to display your location if it is already in the database.
The idea would be that I would make it freely available and have a central place wheer users can upload their databases to be merged together and made available to others.
I was also thinking that it might be a little ambitious as I don't think that there are a hell of a lot of users out there with the proper hardware and the will to comit to this project. Thereby, the location information would be limited but I might do it anyway, if I can sort out the reading of the Cell ID. Just a little pet project I wanted to do for teh past month or two.
If anyone can help witha bit of eVB code for reading the Cell ID, I'd be much obliged.
Regards
Keith Burke
Ireland

RC E100 with Touch HD

Can't get the RC E100 working on the phone. Connecting the remote gives me an error that the phone does not support it. I have tried to install the drivers but that doesnt help me either: you have already the latest drivers.
Anyone?
imo it's not supported, because of the 3.5 jack. I've tried yc-a300 multi adaptor wit no luck either.
i think that i've seen somewhere a reg hack which allows you to use usbExt audio capabilities on htc touch hd.
You would make a lot of people happy if you were able to find this reg hack.
As it stands we are told that no audio is passed to the Ext-USB.
Nogs
ertriel2 said:
i think that i've seen somewhere a reg hack which allows you to use usbExt audio capabilities on htc touch hd.
Click to expand...
Click to collapse
I bought the E100 without realising it wasn't compatable, however, I was poking around in Google and found a reference on a polish version of xda-developers. http://pdaclub.pl. Now, bear in mind that I speak no polish whatsoever, but it seems to be discussing a ROM that has been made which allows the E100 to work with the THD. Here are a couple of very poorly translated excerpts (translated using an online translator), which seem to be talking about using the E100 to control the volume (and hence other controls?):
So, I have noticed (have remarked) that from this a bit requests nazbierało here, whole list beguile that in (to) ) add (be of use for) repair /add ( hope < stuff > sofcie, that in version already 2.1 ) 1. About 1-3% at one changed loudness click, has to act on array china too ( słuchawkowym E100 or change of this parameter for headphones (receiver) only ) 2. Capability of creation in standard player on base of folder ( ) playlisty. Come be give for it from which (who) hard folder song ( ) składanki since all songs are displayed at addition for in bulk < wholesale > playlisty. / 3. Function of voice election should be started up at holding back red headphones (receiver) on pilot (remote control) china 4 ( ) E100.
Click to expand...
Click to collapse
Point 2 certainly < obvious > capability of restoring of (recuperation of) music has given folder - choosing coreplayer if (or) single file from folder mp3 but pilot (remote control) serves for it china only E100 and with (from) exclusively playera touchflo3d.
Click to expand...
Click to collapse
So does anyone speak fluent Polish geek and can create ROMS ? (If there isn't anyone here, I do know a Polish girl who is completely non-technical, but could possibly help with the translation)
Damn it.. wish I read this before ordering the RC E100 in from Amazon in Germany (best price I found).. why the hell do they include a leaflet with the phone advertising these headphones if they are not compatible!!!
Is there no available ROM that can cure this, Dutty etc??!
As for the Polish stuff, my Polish friends are not at all technical either, but I can ask one to translate it too, if anyone will find it helpful...
Does anyone know how we could get a ROM developer interested in this like Dutty? Do we just PM them, or do we need a special invite?
read the manual for the hd (in the wiki)
although the miniusb socket has the extusb pins present, on the inside the extusb pins are not connected
therefore no matter how skilled the hacker, you cant make software to do something that the hardware is not present to deliver
the same with tv out
the extusb port is there purely for bog standard usb functions and charging
if people have a leaflet from an official supplier in their box recommending these headsets/remotes etc, then you have bought them through misleading advertising and you will have some form of recompense through your local trading standards process
jonajuna said:
read the manual for the hd (in the wiki)
although the miniusb socket has the extusb pins present, on the inside the extusb pins are not connected
therefore no matter how skilled the hacker, you cant make software to do something that the hardware is not present to deliver
the same with tv out
the extusb port is there purely for bog standard usb functions and charging
if people have a leaflet from an official supplier in their box recommending these headsets/remotes etc, then you have bought them through misleading advertising and you will have some form of recompense through your local trading standards process
Click to expand...
Click to collapse
Oh, thanks for the info , I'd better try and get a refund
JimLin said:
Oh, thanks for the info , I'd better try and get a refund
Click to expand...
Click to collapse
Hi JimLin,
I don't know if this applies for shipping to foreign countries but in Germany there is a law that you can send back any online ordered goods within 2 weeks without naming even a reason and you will get a refund. (I don't think this applies if you bought by a private seller)
So the odds are on your side I would say...
Best regards,
Tommi
thomasschaz said:
Hi JimLin,
I don't know if this applies for shipping to foreign countries but in Germany there is a law that you can send back any online ordered goods within 2 weeks without naming even a reason and you will get a refund. (I don't think this applies if you bought by a private seller)
So the odds are on your side I would say...
Best regards,
Tommi
Click to expand...
Click to collapse
Good to know, thanks.. Now all I need to do is run amazon.de through Google translate to figure out the returns policy lol

What is this?

Unfortunately I am not allowed to post links since I am too new of a user.
Go to imgur and check out the image who's ID is 4FEMS
(It'd be great if someone could edit a link in)
I once asked about a similar port on the back of my old VN250 dumbphone over on the SparkFun IRC channel at freenode, I recall them mentioning something about it being there so manufacturers could easily write an image to a large number of devices. Is that true? If so/not could this be used to facilitate hacking the device?
I might be able to hack up a connector if I knew what kind of jack that was.
post the link by replacing the : witha a - i couldnt find the pic you talked about
sure thing
http-//i.imgur.com/4FEMS.jpg
Google it.
I am almost certain that this is a "u.fl" interface. If you look on a Wireless NIC you will see the same connector. This connector is for a wireless antenna. You could try connecting an antenna to It. I have one and will tell you the results.
Its for connecting an external antenna, many phones have this somewhere but its usually hard to find and easy to damage if you mess around with it.

[Q] Using hd2 as a external BT or USB soundcard for PC

Hi, folks!
Sorry for the duplicate post in the wrong forum, this here should be the right one.
So to the topic itself:
My old laptop is nearing the end of its lifecycle and now its soundcard got busted and I can't find a way to get it working again.
I could go to a shop to buy an USB-soundcard, but that would be
a) too easy and
b) waste of resources
- as I'm aiming to buy a new laptop soon enough. But until that time I need to hear some sound from the box anyway (some music, some movies and some training videos) so I wonder if it's possible to use the HD2 as a soundcard and get the audio output from its 3,5mm jack. Either by bluetooth or cable connection..
Is there a specific application for this?
phone is running stock winmo 6.5
pc is win7ultimate in intel T7700:2x2.4GHz/4GbRam/500GbHDD box, BT enabled.
Any ideas how it could be done?
Thanks a lot!
Heard of no apps for WM or Android for this type of function.
A USB soundcard can be posted to your door for less than $3 so outlay for a simple fix is minimal but I do like your resourceful approach & hankering for a challenge ...
Mister B said:
Heard of no apps for WM or Android for this type of function.
A USB soundcard can be posted to your door for less than $3 so outlay for a simple fix is minimal but I do like your resourceful approach & hankering for a challenge ...
Click to expand...
Click to collapse
Damn. I was already hoping. So I'll have to drop by a tech store. I do so dislike buying stuff I know I don't need for a long time. And pity, because HD2 produces better audio than my computer ever did (to the headphones)
But thanks for the info anyway.
http://www.senstic.com/android/pocketaudio/pocketaudio.aspx
Give it a while for a few more opinions before you head off to a hardware stall ...

External antenna

I am wondering about the feasibility of constructing an external antenna for the razr. Primarily, is there any way of interfacing with the radio, perhaps through usb, that avoids taking things apart? I'm uncertain of the feasibility behind modding the hardware to any useful extent.
Thoughts?
Its possible to do most anything, however I wouldn't recommend this. You'd have to disassemble the phone, at least down the level of removing the back housing, as I believe the antenna is located with the camera bulge, though I'm not positive. The connector, if there is one, will be very small and delicate, though you may be able to expose the antenna wire itself in order to extend it.
Still, I have no idea how you would make an external antenna without cutting up the case, and everything is extremely narrow and delicate so I'm not sure where you could even pass it through, then you'd have to create some sort of housing for the antenna itself, and I'd imagine you'd want to firmly attach it to the device, seal it, and try to keep it from looking too horrible. That part would be extremely difficult.
I have some experience taking apart phones and other electronics, fixing and upgrading them, and even plan on doing the Maxx conversion as soon as parts are available, but I wouldn't feel comfortable doing this. At the very least I'd wait until spare parts are more readily available, as you'll probably break something. Again, where there's a will there's a way, so if you're comfortable taking electronics apart, study some teardowns, think about your strategy and get everything you need before you start tearing your phone apart, and realize that you do run a significant risk of irreparably damaging your device.
Why do you feel the need to do this? I've found the RAZR's reception to phenomenal, as good or better than anything I had back when phones still had external antennas.
I remember back in the days of me using my Nokia n95, there are modifications to improve GPS reception.. Which requires you opening the phone housing, solder some copper and let the copper wire run around the free space in the housing which improved GPS significantly to allow agps to be switched of but still able to get a lock acceptably fast.
But why on razr? My reception of radio and GPS is very good..
Sent from my Motorola Razr XT910
JehTeh said:
I am wondering about the feasibility of constructing an external antenna for the razr. Primarily, is there any way of interfacing with the radio, perhaps through usb, that avoids taking things apart? I'm uncertain of the feasibility behind modding the hardware to any useful extent.
Thoughts?
Click to expand...
Click to collapse
What for? The signal quality is great by default. If not, you might just need to move.
seanmcd72 said:
What for? The signal quality is great by default. If not, you might just need to move.
Click to expand...
Click to collapse
Agreed
\\Carved into this thread by my RAZR//
http://android-gz.com
I am inclined to agree that it seems a rather tedious and unfeasible task to modify the actual inbuilt phone antenna. This is why I am curious if there is any other possible method of routing a signal to the radio; as best I can determine there seems to be no options aside from modifying the antenna itself.
I would like to note that I have no problems with the phone's reception as-is, but there are some special cases where the ability to attach a large passive antenna would be preferable to using a signal repeater.
LOL, I remember researching the exact same question when I first got my OG Droid.
@OP: Are you talking about Wi-Fi, CDMA (3G), LTE (4G), or just reception in general? I'm not certain, but I don't think it's even possible to build a multi-spectrum auxiliary antennae (especially for anyone who's not an actual engineer). Antennae design is practically an engineering discipline unto itself, and I'm willing to bet money that a home grown antenna would would actually make your reception worse due to interference/signal corruption. Plus, any time you add more than about a foot of antenna length, you have to put in an intermediary signal amplifier, or you'll start dropping packets like crazy. There's just way too much to consider (and trust me, I would freaking LOVE to find a way to do something like this). In the past when mobile technology consisted of more discrete components? Sure. Nowadays in the age of SoC (system on a chip)? Nah ah.
In terms of a USB antenna, I honestly don't know if anyone makes these. If they exist, or if you're such a ninja you manage to build one (let me know if you do :-D ) there's no way to make your device's radio interface with an antenna over USB. Even if it could be done, you'd have to fundamentally rewrite the way Android controls/interfaces with radios (plus write your own drivers), and after all that, you'd be killing your connection speeds by forcing the signal through a software interface prior to being used by the radio itself.
I hate to say something is impossible (we are talking about Android, not friggin' iOS), but let's just say this one is better left alone. That being said, if anyone out there has a degree in electrical engineering and could actually pull something like this off, I'd love to be proven wrong.
If you're having signal issues, I'd suggest researching the factors that can affect the specific connection you're having trouble with. When looking at reception, make sure to compare signal strength using dBm values and not something like how many 'bars' of signal are displayed. The best/simplest solution is to get a wireless range extender and/or cellular signal repeater. Not as much fun as building cool s*** from scratch, I know. Guess it depends whether you're looking for a destination or a journey.....
Sent from my Droid Razr Maxx
jptaktix101 said:
LOL, I remember researching the exact same question when I first got my OG Droid.
@OP: Are you talking about Wi-Fi, CDMA (3G), LTE (4G), or just reception in general? I'm not certain, but I don't think it's even possible to build a multi-spectrum auxiliary antennae (especially for anyone who's not an actual engineer). Antennae design is practically an engineering discipline unto itself, and I'm willing to bet money that a home grown antenna would would actually make your reception worse due to interference/signal corruption. Plus, any time you add more than about a foot of antenna length, you have to put in an intermediary signal amplifier, or you'll start dropping packets like crazy. There's just way too much to consider (and trust me, I would freaking LOVE to find a way to do something like this). In the past when mobile technology consisted of more discrete components? Sure. Nowadays in the age of SoC (system on a chip)? Nah ah.
In terms of a USB antenna, I honestly don't know if anyone makes these. If they exist, or if you're such a ninja you manage to build one (let me know if you do :-D ) there's no way to make your device's radio interface with an antenna over USB. Even if it could be done, you'd have to fundamentally rewrite the way Android controls/interfaces with radios (plus write your own drivers), and after all that, you'd be killing your connection speeds by forcing the signal through a software interface prior to being used by the radio itself.
I hate to say something is impossible (we are talking about Android, not friggin' iOS), but let's just say this one is better left alone. That being said, if anyone out there has a degree in electrical engineering and could actually pull something like this off, I'd love to be proven wrong.
If you're having signal issues, I'd suggest researching the factors that can affect the specific connection you're having trouble with. When looking at reception, make sure to compare signal strength using dBm values and not something like how many 'bars' of signal are displayed. The best/simplest solution is to get a wireless range extender and/or cellular signal repeater. Not as much fun as building cool s*** from scratch, I know. Guess it depends whether you're looking for a destination or a journey.....
Sent from my Droid Razr Maxx
Click to expand...
Click to collapse
Sorry, I should have mentioned that my sole concern in this case is the gsm band, and I am unconcerned with maintaining a data connection.
As far as designing the actual antenna goes, it is non-issue. I am currently studying electrical engineering myself, and my father has been working in the field for around thirty years and can assist with any hangups, if necessary. My primary concern, again, is interfacing with the device. If there proves to be no reasonable way to accomplish this, then I will likely end up constructing a signal repeater. Unfortunately, that is a good deal more tedious than a passive antenna and (hopefully) relatively little coding.
My apologies sir, I think you may know way more about this than I do. You're much better equipped than I am to tackle something like this. I studied mechanical engineering and computer science so I understand some basic EE principles (which I use to stumble through things like overclocking), but my strong suit is most definitely on the intangible soft(ware) side.
Anyway, what I said about using a USB interface still stands. There is a bi-directional pathway between your phone's USB interface and the cell radio (as seen in contexts such as internet connection sharing over USB), so in a highly theoretical sense it should be possible to programmatically facilitate the kind of communication you want. But the devil, as you know, is in the details.
There are a million potential obstacles, the greatest of which may be trying to procedurally disable input from the internal antenna while your passive auxiliary antenna is connected. If you're willing to sacrifice signal latency and a ton of CPU cycles you could theoretically run the radio input through an algorithmic filter before feeding it to the system (I doubt even a dual core mobile processor would be able to sustain a logic based signal filter and it's operating system simultaneously. If only the Razr had a Tegra 3 chipset....). Utterly no idea if this is doable. I would highly recommend reading what's relevant on the Android Developers site as a starting point, and then working your way back through the fundamentals of Linux/Unix (at this point you will know infinitely more than I do). That's the most efficient method I can think of for assessing Android as a viable platform, if you can't get a definitive answer.
It's worth mentioning that obtaining unadultered design specs for the SoC/board/handset/etc can be really hard to dig up nowadays unless you've got an inside source (anyone have a friend who's 'in the know' they'd like to share?).
Anyway, I can't believe I type this entire freaking thing on my phone...
To implement a modification like this would take a much higher degree of practical expertise in ground-up development than I possess, so I can't tell you much else. But this site is a breeding ground for world-class genius. If there is someone in the world who can help you, he posts on this forum.
Sent from my Droid Razr Maxx
I would not see the need? The radio/signal strength on the razr is among the best available. Motorolas have always been known for great signal strength/reception.
Sent from my DROID RAZR using xda premium
Adauth said:
I would not see the need? The radio/signal strength on the razr is among the best available. Motorolas have always been known for great signal strength/reception.
Sent from my DROID RAZR using xda premium
Click to expand...
Click to collapse
Lolz at Adauth...thanks for helping! Read any posts lately?
Sent from my Droid Razr Maxx
JPtheSmith said:
Lolz at Adauth...thanks for helping! Read any posts lately?
Sent from my Droid Razr Maxx
Click to expand...
Click to collapse
"Lolz" right back at you. Grow up.
Sent from my DROID RAZR using xda premium
JPtheSmith said:
My apologies sir, I think you may know way more about this than I do. You're much better equipped than I am to tackle something like this. I studied mechanical engineering and computer science so I understand some basic EE principles (which I use to stumble through things like overclocking), but my strong suit is most definitely on the intangible soft(ware) side.
Anyway, what I said about using a USB interface still stands. There is a bi-directional pathway between your phone's USB interface and the cell radio (as seen in contexts such as internet connection sharing over USB), so in a highly theoretical sense it should be possible to programmatically facilitate the kind of communication you want. But the devil, as you know, is in the details.
There are a million potential obstacles, the greatest of which may be trying to procedurally disable input from the internal antenna while your passive auxiliary antenna is connected. If you're willing to sacrifice signal latency and a ton of CPU cycles you could theoretically run the radio input through an algorithmic filter before feeding it to the system (I doubt even a dual core mobile processor would be able to sustain a logic based signal filter and it's operating system simultaneously. If only the Razr had a Tegra 3 chipset....). Utterly no idea if this is doable. I would highly recommend reading what's relevant on the Android Developers site as a starting point, and then working your way back through the fundamentals of Linux/Unix (at this point you will know infinitely more than I do). That's the most efficient method I can think of for assessing Android as a viable platform, if you can't get a definitive answer.
It's worth mentioning that obtaining unadultered design specs for the SoC/board/handset/etc can be really hard to dig up nowadays unless you've got an inside source (anyone have a friend who's 'in the know' they'd like to share?).
Anyway, I can't believe I type this entire freaking thing on my phone...
To implement a modification like this would take a much higher degree of practical expertise in ground-up development than I possess, so I can't tell you much else. But this site is a breeding ground for world-class genius. If there is someone in the world who can help you, he posts on this forum.
Sent from my Droid Razr Maxx
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I was always under the impression that in the case of tethering, android was not so much handing over the entire radio connection, but instead providing an application with Internet access, which that application then "passed on" through the usb or wifi modules. If this is not the case, then perhaps there may be something here. Otherwise, I am uncertain if this is feasible. Essentially building a "virtual radio" strikes me as unlikely to work, due to, as you mentioned, the fact that it would likely require considerable processing power in addition to a great deal of programming work.
Adauth said:
"Lolz" right back at you. Grow up.
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Dude, lighten up. I was just messing with you.
Anyway, I'm pretty sure you're right: without a lot of programming there's no chance of doing this (and probably not even then). Looks like you're only option is to go analog....BTW, is this project part of an assignment, or is it just for fun?
Sent from my Droid Razr Maxx
Not part of an assignment. And I've been looking into it, the choices are basically as follows:
-Build an inline switch that enables either the current antenna or an external port, into which an antenna can be wired
-construct a device that essentially mirrors the current antenna and supporting hardware, and *possibly* find a way to interface to this via software over usb
-use an active repeater
So I think it's safe to say that a (relatively) simple hardware modification is the ideal solution in this case.

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