Fun with resistors (home/car dock mode + more)

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By TheBeano, Senior Member on 26th October 2010, 09:39 PM
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16th April 2015, 06:13 PM |#221  
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Originally Posted by darkspr1te

No, each value triggers that one mode, be careful about injecting power when the device is a output power mode, something could get fried.


Is there any way to force MHL mode by software, without using resistors?
16th April 2015, 06:19 PM |#222  
darkspr1te's Avatar
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There would be no point as the mhl output would not reach the usb, it would go nowhere.
28th January 2018, 12:26 AM |#223  
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Looks like the resistor(s) are actually inside the AnyWay box, instead of the usb-c plug.
As you can see in the pinout diagram, line CC is connected to the DB25 header which in turn connected to the box.
So, if anyone has the AnyWay box, the usb-c test cable, and an ohm meter they can simply measure the resistance between ground and pin 23 of the DB25 header. This way we could replicate a test cable without the expensive test jig.

I have played around with the "standard" test resistor values (300k, 523k, 619k etc) between line CC and Gnd, but wasn't able to get any results, not even download mode using a 300k resistor which works on all micro-usb phones. Either usb-c is using different values or there's something else we're missing here.
However, an interesting observation I've made, is that when flashed with combination firmware, the phone accepts most of these low level uart/modem test commands through the usb-c modem port (not the usb-serial port!) via a standard terminal (sometimes they need to be sent a couple of time for it to take, and also dialed *#0*# for test mode):

AT+GMM (Model number)
AT+HWINDICK (CPID S7 and newer)
AT+FACTORST (Warning: Forces a factory reset!)
AT+FUS? (DL mode)
AT+SIZECHECK (Storage info)
AT+SIZECHECK=1,0 (Storage info)
AT+SVCIFPGM=1,1 (Short Info)

Read commands:
AT+<command> - read
AT+<command>? - read
AT+<command>=1,0 - read
For example:
AT+PRECONFG=1,0 - reads CSC config

Write commands:
AT+<command>=2,<info> - write
For example:
AT+PRECONFG=2,XAS - writes CSC config

Hope someone steps up to the plate, and gives us the correct resistor value between CC and GND on usb-c
Thanks in advance.
2nd August 2018, 12:41 PM |#224  
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It seems a static topic.
Any idea anybody regarding to the resistor list for a usb-c?
I am interested for activating dock mode (car or home) on a smartphone.
8th August 2018, 06:59 AM |#225  
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Originally Posted by TheBeano

Update 6 March 2011: Confirmed modes so far:
Desk Dock: 365K (also works with 1K)
Car Dock: 619K

in the OP ?
4th April 2019, 08:30 PM |#226  
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Just for information, all values can be found on FSA9480 datasheet:

The FSA9480 is a USB port accessory detector and
switch. The FSA9480 is fully controlled using I2C and
enables USB data, stereo and mono audio, video,
microphone, and UART data to use a common
connector port. It is designed for compatibility with CEA-
936-A car kit adapters, USB 2.0 signaling, and USB
OTG (on-the-go). The architecture is designed to allow
audio signals to swing below ground so a common USB
and headphone jack can be used for personal media
players and portable peripheral devices.

Note: on page 13 there are some other values I don't quite understand.
Can someone have a look?
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5th April 2019, 09:53 AM |#227  
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Fairchild can write whatever descriptions they like. The true usage of them depends on the bootloader by Samsung.
And thanks for the datasheet. I should have guessed myself.
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