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Topic: Archer C5 unable to type into serial - resistor voltage ?

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Hello everyone,

I have read other people with the same router unable to type anything in the serial as they were getting 0 volt on TX and therefore they had to solder a resistor from TX to VCC in order to be able to type into serial console.

I guess I am in the same situation.

I am wondering if anybody knows what is the resistor voltage I need to solder. I read of somebody guessing 10k ohms, but I'd rather be sure and avoid frying it up.

Thanks

(Last edited by Latrina on 12 Aug 2015, 16:11)

DerBernd wrote:

Hi Latrina,

I believe I've got a similar issue with the Archer C7 v2.0 when I use a MAX3232 adapter (id=58982).

How do you connect to the UART?

I tried USB TTL adapters (http://www.amazon.de/dp/B008AGDTA4 / http://www.amazon.de/dp/B008RF73CS). Both worked fine.


Regards

Hi,

my USB Serial TTL is a FTDIBUS\COMPORT&VID_0403&PID_6001 (sorry I don't have a linux distribution handy atm).

The way I have connected is RXD (white wire)> TXD (green wire)>  GND(red wire) and here is the picture http://tinyurl.com/pmd2847 .

On the other hand at the computer I am using Xshell as application terminal and I set it on COM3(which is the one used by the UART), Baud Rate 115200, Data bits 8, Stop Bits 1, no Parity and no Flow Control.

Additionally I believe this UART TTL Serial I have doesn't do 3.3Vcc but only does 5v. I have successfully used it on a TP-Link TL-WR2543ND without the need of 3.3Vcc.

I am really frustrated because I am not sure if I need to buy a different USB UART serial or if I need to solder a resistor that I don't even know the voltage yet.

Thanks

ReHi,

the board looks quite similar to mine. I don't know Xshell, but the settings should work. VCC is not needed in this case.

Have you tried swapping RxD/TxD?

Regards,
Bernd

Latrina wrote:

I am wondering if anybody knows what is the resistor voltage I need to solder. I read of somebody guessing 10k ohms, but I'd rather be sure and avoid frying it up.

10k seems the right value for other routers, so it should be fine. Since you use the routers Vcc, which is 3,3 V, you can't damage the device by using any other resistance, as that is the same voltage of the serial adapter. The resistance mainly matters to meet the voltage levels that the router can sense as distinct high or low.

DerBernd wrote:

ReHi,

the board looks quite similar to mine. I don't know Xshell, but the settings should work. VCC is not needed in this case.

Have you tried swapping RxD/TxD?

Regards,
Bernd

I tried already but nothing shows up.

MBS wrote:
Latrina wrote:

I am wondering if anybody knows what is the resistor voltage I need to solder. I read of somebody guessing 10k ohms, but I'd rather be sure and avoid frying it up.

10k seems the right value for other routers, so it should be fine. Since you use the routers Vcc, which is 3,3 V, you can't damage the device by using any other resistance, as that is the same voltage of the serial adapter. The resistance mainly matters to meet the voltage levels that the router can sense as distinct high or low.

I do apologize for the extremely late reply but I have been quite busy with work and family lately.

I stumbled upon this USB TTL adapter that is capable of doing both 3.3V and 5V, would I be able to type into serial using this adapter with 3.3V VCC connected, or would I still need to sold a resistor anyway?

Thanks

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