Bypassing GL850/852 chip for a better stable USB? - MTCD Android Head Units General

Hi,
After seeing many users struggle with this chip... GL852 is better but some still has some issues randomly with it.
I was wondering why not take the only USB directly from the PX3/5/6 board to external USB connector and then manage all USB device externally with a good quality powered USB hub?
This should work in theory, but you will lose internal WIFI (can be easily corrected with a WIFI dongle)
What do you think guys?
Regards,
Laurent

Not struggling here . Also, wifi is via separate USB connection according to MTCD schematic and at least my unit is like this.
My understanding is that some units came with defective USB hub chips, replacing them solves an issue where they slow initialize when cold.

marchnz said:
Not struggling here . Also, wifi is via separate USB connection according to MTCD schematic and at least my unit is like this.
My understanding is that some units came with defective USB hub chips, replacing them solves an issue where they slow initialize when cold.
Click to expand...
Click to collapse
Yes I just saw in the schematic and tested the two last pins 74/75 are in fact connected directly to the wifi board (RTL8188ETV).
Since I'm already board opened... I will remove the chip I'm already using a special hub in the car for Android Auto that can deliver 2.1 amp while using USB data.

Just a quick follow-up... I double checked all the traces from the GL850 3 ports goes at the back of the unit one very important port (USB-DM4,USB-DP4) goes at the front LCD for touch input!
TL;DR : Don't try to bypass the GL850/852 chip or you will lose touch input!

Related

[Q] USB host? Is it possible with the a100?

Hello friends, I am new to this forum, but certainly not new to the tablet world. I purchased the iconia a100 a few weeks ago and I must say it is a superb tablet in almost everyway. That being said, I am trying to come up with a solution for the lacking usb host on this tablet. I am certainly not a dev, but I am wondering if there is anything in the works for a working usb host? Does anyone know if acer has any plans to offer an adapter or even a different docking station with the usb host working from the 40 pin? If anyone has any ideas or would like to start a project i will be glad to help in anyway I can. While i was researching this usb host problem i see that there was a very sinilar situation with the galaxy which has since been resolved. Any suggestions? Thanks
Not yet possible, but you can pretty much count on it to be baked into a custom ROM when we get the ability to fully unlock and root this device. Root is already possible, and done. Unfortunately, we cant really do much development on it right now due to the encrypted bootloader. Most devs are waiting for the ics update in January to get the ball rolling on tweaks and hacks to the a100.
Sit tight, they'll have you up and running in no time
ummmmm............ could you repeat that?
This is also #1 on my wishlist. However, I don't know if that is even possible with a custom ROM; it requires the hardware to support it and I don't recall seeing any teardown that states that it would be possible.
I've seen it done in various phones, but don't know if its been posted on any here, but I'm sure a search on the forum would help find them. Its a matter of reconfiguring the port in the programming and getting an adapter from micro USB to standard USB.
But don't quote me on any of this, I could be mistaken with other devices. There has been talk about USB hosting on the a100 before.
ummmmm............ could you repeat that?
Yes, you would need something called an OTG (on the go) adapter. The hardware in the device has to support host, so it is not JUST software.
I can confirm that i have tried the otg adapter as well as other adapters...and it only works as slave. I would just like someone to confirm that usb host is possible [that the harware supports host capabilities]. I am just glad to see there are more people interested in fixing this problem as this tablet is superfast and top quality in every other way in my opinion. Thanks again
Maybe something comes out of
http://www.circuitsathome.com/mcu/programming/android_adk_compatible_usb_host_library_release
I ordered an OTG cable and once it comes I will take a look at enabling USB host mode.
I am guessing that the hardware supports USB host, but will need a kernel module and some scripts to enable it.
I also suspect that the USB port will not supply power to an attached device. If this is the case, the workaround is to attach a powered USB hub to the OTG cable.
Crossing my fingers, and waiting for that OTG cable to come in the mail...
flar2 said:
I ordered an OTG cable and once it comes I will take a look at enabling USB host mode.
I am guessing that the hardware supports USB host, but will need a kernel module and some scripts to enable it.
I also suspect that the USB port will not supply power to an attached device. If this is the case, the workaround is to attach a powered USB hub to the OTG cable.
Crossing my fingers, and waiting for that OTG cable to come in the mail...
Click to expand...
Click to collapse
USB host is enabled in the kernel. Hardware does support USB host.
Acer left it off the board entirely, so I doubt much can be done without hardware modding, which I'm all for lol.
Tapatalked from my Galaxy S II.
Sounds grim if the hardware connection is not there, are we sure that the port is just not supplying power?
do the kernel modules load? (e.g. usb-hid, usb-storage)
Has anyone actually tried to:
a) insmod the correct modules
b) force change to host mode (the device probably has to be either slave or host, not both at once)
c) connect something (e.g. a mouse or a thumbdrive) through the otg cable and a powered usb hub?
At least I won't have to build a kernel to test this out.
flar2 said:
Sounds grim if the hardware connection is not there, are we sure that the port is just not supplying power?
do the kernel modules load? (e.g. usb-hid, usb-storage)
Has anyone actually tried to:
a) insmod the correct modules
b) force change to host mode (the device probably has to be either slave or host, not both at once)
c) connect something (e.g. a mouse or a thumbdrive) through the otg cable and a powered usb hub?
At least I won't have to build a kernel to test this out.
Click to expand...
Click to collapse
I know this comes up every now and then, I really dont know how far anyone gets before giving up. Feel free to try out whatever you want, while I don't care about USB host I know a lot of people do and would love an update on any progress anyone can make. Even if its just things that don't work.
Acer is generally lazy and cheap, we use the same kernel source as the a500 which has host, which is why we also have it. It could be modules, though I doubt its so simple. Also a powered hub would be needed, there is no power supplied to the port that anyone has found. This could be remedied with some hardware work I'm sure. The hub would also need to be one way, meaning not dumping power to host as I doubt the a100 will take it and without protection would likely suffer damage if the power pins are even hooked up.
The system itself runs at 12v though I'm sure there's a 5v rail someplace but if it can support powering anything past maybe a flash drive is unknown.
Take a visit to iconia-dev on free node, they'll know more of this then probably anyone here does lol
Tapatalked from my Galaxy S II.
The A500 does not implement USB otg, but rather a standard USB port. In other words, USB otg is not necessary for the A500 since it has a standard port. The USB otg standard allows a the port to act as both master and slave depending on the connection. In the A100 service manual, the schematic shows only one connection to the chipset (client), host is unconnected, which could be a problem. However, it is known that the Tegra 2 can support otg connections. I'm not certain, but it may be possible that by shorting pins 4 and 5 in the micro usb connector (ie, using an otg cable) and with the proper kernel level support, the A100 could still act as a USB host, albeit with no power supply to the micro USB port.
I'll continue to investigate this once I have a chance to build otg support into the kernel and recieve the otg cable.
flar2 said:
The A500 does not implement USB otg, but rather a standard USB port. In other words, USB otg is not necessary for the A500 since it has a standard port. The USB otg standard allows a the port to act as both master and slave depending on the connection. In the A100 service manual, the schematic shows only one connection to the chipset (client), host is unconnected, which could be a problem. However, it is known that the Tegra 2 can support otg connections. I'm not certain, but it may be possible that by shorting pins 4 and 5 in the micro usb connector (ie, using an otg cable) and with the proper kernel level support, the A100 could still act as a USB host, albeit with no power supply to the micro USB port.
I'll continue to investigate this once I have a chance to build otg support into the kernel and recieve the otg cable.
Click to expand...
Click to collapse
Thanks for that, but one thing, its already in the kernel. However Linux society and/or waydownsouth would know more about what's in there, I just know it isn't blocked there. Modules etc I don't know. I look forward to seeing some progress on this topic.
Tapatalked from my Galaxy S II.
Pulled the kernel config from my tablet, you are correct, otg support is built into the kernel.
I'm using ezterry's kernel, almost everything is built in, there are only a few modules that have nothing to do with this.
I tested with an OTG cable, which shorts pins 4 and 5 in the micro usb connector. As expected, this did not enable USB host mode.
I tested wtih 5V going into the micro usb connection, as some of the non-powered devices need that voltage applied to activate the port, still nothing. (and no damage!)
I added a few other things to the kernel, the dmesg output changed slightly compared ezterry kernel
When connecting otg cable with 5V, dmesg shows:
tegra-otg tegra-otg: SUSPEND --> PERHIPHERAL
vbus connected, lock wakelock
tegra-otg tegra-otg: PERHIPHERAL --> SUSPEND
tegra_usb_phy_power_off(inst:0), phy->regulator_on: 1, line : 2754
tegra_usb_phy_power_off(inst:0), tegra_get_revision(): 0
vbus disconnected, unlock wakelock
android_work: did not send uevent (0 0 (null))
In the possibility that USB host is not possible on the micro usb port, a hardware mod could be done. There are points for a mini PCI-E connector on the motherboard (this is where the 3G module would be for A101). Solder wires to pins 36 and 38 for USB data, 4 for ground and connect them to a usb port. The PCI-E only gives 3.3V, but power could be supplied by a powered hub instead. There is even space inside the unit to mount a micro usb connector on the end with the power button.
The main roadblock is that the solder points are on the back side of the pcboard so you have to fully disassemble the unit to remove the motherboard. It would actually be fairly easy to do if the points were showing when you remove the back cover.
I don't think I have the nerve to actually try this.
flar2 said:
In the possibility that USB host is not possible on the micro usb port, a hardware mod could be done. There are points for a mini PCI-E connector on the motherboard (this is where the 3G module would be for A101). Solder wires to pins 36 and 38 for USB data, 4 for ground and connect them to a usb port. The PCI-E only gives 3.3V, but power could be supplied by a powered hub instead. There is even space inside the unit to mount a micro usb connector on the end with the power button.
The main roadblock is that the solder points are on the back side of the pcboard so you have to fully disassemble the unit to remove the motherboard. It would actually be fairly easy to do if the points were showing when you remove the back cover.
I don't think I have the nerve to actually try this.
Click to expand...
Click to collapse
Well if you want to play it like that, you can use a mini pci-e > usb adapter, which is also available with and without sata too lol. It would, maybe, depending on the board used, even line up with the sim slot, so minimal case cutting would be needed to make it accessible for usb. Straight drop in for an A101, though we lack the actual slot for it. Might be something I'll try later on.
Edit: I forget, does the sim slot line up with the pci-e slot? Been awhile since I saw the inside of one, so I may be wrong on that point.
There isn't an actual mini pci-e connector in my tab, it's just the solder points, so you would have to solder on a connector to use the adapter. The sim slot doesn't line up. But it looks like the empty sim slot is not high enough for a micro usb port to fit anyway.
I tried the hardware mod. Unfortunately the mini pci-e is not hooked up to the system. In other news, the motherboard is very easy to remove and reinstall.
there is a ROM in which they have implemented the usb otg?
Inviato dal mio Galaxy Nexus con Tapatalk 2

Take usb mouse/keyboard to bluetooth. (motorola lapdock related)

with all the coverage the motorola laptop has been getting these days (google: motorola lapdock rikomagic or motorla lapdock raspberry pi )
I got one to toy around with it my self. I'd really like it to work with MHL devices. Thats the moment I found out that MHL's micro usb in is to charge the device and get the HDMI out to work, but doesn't pass though and more usb data though. I imagine the bandwidth is too great.
So as a consolation I thought it would be cool if the lapdock's mouse and keyboard were bluetooth, then i could connect to its display with hdmi, and control the phone with the bluetooth input.
Does anyone know if there is a generic usb device that allows you to connect a USB keyboard and mouse and then transmits though bluetooth? alternatively does any one know of any relevant mods that might help me hack this together?
The problem with MHL is that it uses the electrical path from the USB connection.
The problem is not bandwidth, it's wires.
All of the funny things that plug into a micro USB connector just use the same 5 pins that are already there and repurpose them.
This includes "Carkit", which is the analog headset/ handsfree connection or MHL.
usb flash is also possible to connect and then not get what you
If you wanted to be really hard-core you could add another micro USB connector to your phone.
You'd have to pick off the USB signals as they come out of the PHY interface and before the main connector multiplexer.
Or you could get the guts out of a trashed BT keyboard and wire it to your Lapdock keyboard.
You wouldn't have to get the layout correct, you could just fix /system/usr/keylayout.
gltovar said:
...Does anyone know if there is a generic usb device that allows you to connect a USB keyboard and mouse and then transmits though bluetooth? alternatively does any one know of any relevant mods that might help me hack this together?
Click to expand...
Click to collapse
I looked and haven't found one. However, during the search I found the KBtalKing Pro mechanical keyboard that solved my problem (well, when it is officially released next month)--it will allow me to use it as my main desktop keyboard (which should be great to type on due to the use of mechanical keys), and also pairs up to 10 devices via Bluetooth as well as one main USB device (probably the main computer). Looks like I'd be able to type on my Android, iPhone 4, PC or Mac simply by pressing a couple of buttons on the keyboard to switch over.
Probably not the economical USB to BT conversion you were looking for, but it's a solution and then some.
You can check out handheldsci com/kb it looks like what you want.
Hi,
Did someone try up this handheldsci adapter ?? It looks indeed as the solution to use any input device/combo without using the usb connection (very useful for smartphones).

Issues with Ethernet and Micro USB ports

The ethernet port on my KS Ouya seems to not be correctly attached to the board and thus can be moved up and down a lot. I've also noticed that it has no way of locking an ethernet cable in. On top of that i've noticed that the micro usb port used to connect the ouya to a pc only allows cables to go halfway in and the contact is sketchy at best (as of now I have yet to get the connection to stay for more than a few seconds).
Has anyone else ran into these issues, or is mine just a manufacturing defect and should be replaced?
I have the same problem with the micro usb port. My Samsung cables plugs are too short, but I have a slightly longer plug on my Kodak cable from a pocket videocam.
Sent from my SCH-I535 using Tapatalk 4 Beta
I've heard others over on ouyaforum complaining about similar issues, so you're not alone. I don't have any of these problems myself. I wish you luck getting it resolved!
Thanks for the replies JLCollier and Tadeo. The micro usb port issues turned about to be just that specific cable (weird).
Regarding my ethernet port, i'll probably try contacting support, see if they can send a replacement board. Will post here if I can get them to replace it; maybe others with the issue will be able to succeed too.
Kiba Urufu said:
Thanks for the replies JLCollier and Tadeo. The micro usb port issues turned about to be just that specific cable (weird).
Regarding my ethernet port, i'll probably try contacting support, see if they can send a replacement board. Will post here if I can get them to replace it; maybe others with the issue will be able to succeed too.
Click to expand...
Click to collapse
in regards to the thernet port, has anyone been able to exclusivly use ethernet in stead of wifi? I noticed that some apps/games will give me a not connected to wifi error even though im hard lined.
Ramzes13 said:
in regards to the thernet port, has anyone been able to exclusivly use ethernet in stead of wifi? I noticed that some apps/games will give me a not connected to wifi error even though im hard lined.
Click to expand...
Click to collapse
I use the ethernet exclusively 99% of the time, but there are some sideloaded apps that require either wifi or mobile network (which we don't have), so at that point I switch over to Wifi. Nothing on the OUYA itself should require wifi, however.
With both ethernet and wifi connected, wifi seems to take priority.
For example, transferring local files only achieves 1mb per second (which is what i'd expect on wifi)
Ethernet should get close to 10mb per second.
Hopefully they are working on a fix for this.

RK3188 1024x600 front USB not working? Any workarounds?

I'm not able to get to the bootloader screen because the front usb port is not functioning on my unit. Has anyone been able to use one of the USB ports on the back to get to ADB and/or get to the bootloader? Is this a known issue with a workaround? I've done quite a bit of searching and have not turned up any solutions. Considering what is involved in shipping this back, I'd much rather figure something out. Thanks in advance for any help!
Edit: I should mention that I have used the adbon password and it does acknowledge that adb has been enabled. Just nothing seems to work on the front port. When I connect my Linux machine and run lsusb nothing shows for the unit. I have considered buying or making a USB-A to USB-A cable to connect my computer to one of the back USB ports, but I'm concerned about how these back USB ports are designed. Is it as simple as a built-in OTG cable? If so I'm probably fine. If it is more like a computer's USB port I could damage my laptop, my headunit, or both. I'd really like to hear if anyone else has had to deal with this. Unfortunately I haven't verified if the front USB will charge a phone. This is my next step.
dutchhome said:
I'm not able to get to the bootloader screen because the front usb port is not functioning on my unit. Has anyone been able to use one of the USB ports on the back to get to ADB and/or get to the bootloader? Is this a known issue with a workaround? I've done quite a bit of searching and have not turned up any solutions. Considering what is involved in shipping this back, I'd much rather figure something out. Thanks in advance for any help!
Edit: I should mention that I have used the adbon password and it does acknowledge that adb has been enabled. Just nothing seems to work on the front port. When I connect my Linux machine and run lsusb nothing shows for the unit. I have considered buying or making a USB-A to USB-A cable to connect my computer to one of the back USB ports, but I'm concerned about how these back USB ports are designed. Is it as simple as a built-in OTG cable? If so I'm probably fine. If it is more like a computer's USB port I could damage my laptop, my headunit, or both. I'd really like to hear if anyone else has had to deal with this. Unfortunately I haven't verified if the front USB will charge a phone. This is my next step.
Click to expand...
Click to collapse
My front USB also doesn't work. I even got mini to standard USB cable with unit, but plugging flash drive into it doesn't produce any reslt.
I also plugged extension cable to one of back USB ports and tried it (plugibg same USB flash) but it doesn't work either.
So I'm also confused.
Does that mean you are still running the stock ROM? I have been hesitant to install the custom ROM because they say you must be able to get into the bootloader even though I couldn't find a step in the process that required it.
Regarding the USB ports not working at all, you may find that you need to use a powered USB hub. I've seen reports of USB devices acting up due to the low power. This is one of the reasons I thought it might be safe to use the rear ports with my computer. (My first real test is going to be mangling a male-to-male USB cable so only the data lines are connected to see if I can get those rear USB ports to talk to the computer. I figure that way there is no chance of frying any circuits.. Each side already has its own power and I don't believe any signaling is sent via the power pins.)
On my unit (MTCB-KGL-V2.80), I have used a T-Mobile USB broadband modem successfully on the rear port, so I know rear ports are live. I did take it apart to see if something was obviously wrong with the front port, but nothing jumped out at me.
So I have a bit more information on my headunit. BTW, I have the BMW E46 model with MCU MTCB-KGL-V2.80.
On my system, both the front USB port and the rear 3G USB port are wired as device ports connected to an AU6258 USB controller (http://www.sunnyqi.com/upLoad/product/month_1403/201403162331285643.pdf). I don't remember exactly which USB ports they are connected to, but I believe the 3G port is connected to port 2 (pins 6 & 7) and the front USB port is connected to either ports 3 or 4 (pins 9 & 10 or 11 & 12 respectively). Nothing is connected to port 1 or to the upstream port. The other rear USB port is wired directly to the MTC_RK3188 board.
All three ports are wired with only four pins, so I'm concerned that none of them could work with the computer. The USB controller doesn't have USB ID pins, so does that mean that the 4 downstream ports are OTG and the upstream port is for a computer? Unfortunately I don't know the hardware side.
dutchhome said:
Does that mean you are still running the stock ROM? I have been hesitant to install the custom ROM because they say you must be able to get into the bootloader even though I couldn't find a step in the process that required it.
Regarding the USB ports not working at all, you may find that you need to use a powered USB hub. I've seen reports of USB devices acting up due to the low power. This is one of the reasons I thought it might be safe to use the rear ports with my computer. (My first real test is going to be mangling a male-to-male USB cable so only the data lines are connected to see if I can get those rear USB ports to talk to the computer. I figure that way there is no chance of frying any circuits.. Each side already has its own power and I don't believe any signaling is sent via the power pins.)
On my unit (MTCB-KGL-V2.80), I have used a T-Mobile USB broadband modem successfully on the rear port, so I know rear ports are live. I did take it apart to see if something was obviously wrong with the front port, but nothing jumped out at me.
Click to expand...
Click to collapse
No I flashed Malaysk ROM from GPS SD card. No problems. Just follow instruction. I had luck that I didn't need to recover from USB.
Did you tried with USB powered hub? I don't have one to try it myself.
RK3188 1024x600 front USB not working confirmed
pa.ko said:
My front USB also doesn't work. I even got mini to standard USB cable with unit, but plugging flash drive into it doesn't produce any reslt.
I also plugged extension cable to one of back USB ports and tried it (plugibg same USB flash) but it doesn't work either.
So I'm also confused.
Click to expand...
Click to collapse
I checked on my Linux workstation with
Code:
lsusb |wc -l
plugging and unplugging all three USB cables and the number did not change. BTW where did you use the "adbon" command? The only place that I could even try was at Settings > Factory Settings. Regards Flint

Problems with USB connection

I had been somewhat unlucky and while charging my beloved FLO something went puf (literally). After that I don't have any USB connectivity. Charging my N7 works (very slowly), but no USB OTG or USB ADB. OK Fine and dandy if I wouldn't be total idiot and wipe system while trying to install new ROM before transferring ROM image to internal storage.
Now I have FLO paper clip able to go to TWRP but can't install nothing. As far I understand there's no way to enable wifi in TWRP.
Any ideas what would needed to be replaced to make my FLO work again so I can put some ROM on it and make it work again.
I'm not sure if USB daughter board would suffice and solve my problem. Any suggestions?
jxl69 said:
I had been somewhat unlucky and while charging my beloved FLO something went puf (literally). After that I don't have any USB connectivity. Charging my N7 works (very slowly), but no USB OTG or USB ADB.
Click to expand...
Click to collapse
Either the USB port developed "dry joints" or the wide silver cable (LCM) needs to be re-seated on both connectors.
Disconnect the battery before fixing LCM cable. Here is advice on USB port repair.
Replacing the daughterboard PCB should be the last resort because it is unlikely that the touch function will work 100%. It would work if we had access to the touch calibration software - the problems are described here https://forum.xda-developers.com/ne...rivers-to-calibrate-touch-screen-usb-t3334898
k23m said:
Either the USB port developed "dry joints" or the wide silver cable (LCM) needs to be re-seated on both connectors.
Disconnect the battery before fixing LCM cable. Here is advice on USB port repair.
Replacing the daughterboard PCB should be the last resort because it is unlikely that the touch function will work 100%. It would work if we had access to the touch calibration software - the problems are described here https://forum.xda-developers.com/ne...rivers-to-calibrate-touch-screen-usb-t3334898
Click to expand...
Click to collapse
I doubt re-seating would help or cleaning USB port, since it was something electrical happening with that *puf*. If my memory serves me right there was a smell of burnt electronics. I doubt that some shortage disconnected any cables.
jxl69 said:
I doubt re-seating would help or cleaning USB port, since it was something electrical happening with that *puf*. If my memory serves me right there was a smell of burnt electronics. I doubt that some shortage disconnected any cables.
Click to expand...
Click to collapse
Sounds like you need a new charging port and board. Easy to fit but difficult to get hold of one. Maybe purchase a broken Flo on eBay and extract the charging port board
dave457 said:
Sounds like you need a new charging port and board. Easy to fit but difficult to get hold of one. Maybe purchase a broken Flo on eBay and extract the charging port board
Click to expand...
Click to collapse
Even tho charging works? The only problem is data part of USB connection. USB OTG will not work neither will it connect to a PC for file transfer/adb. But if connected to PC or plug device charges. I believe it will not charge past 80 or 90%.
jxl69 said:
Even tho charging works? .
Click to expand...
Click to collapse
Yes

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