[SOLVED] LynxTerm finds the port but cannot open it

Lynxmotion Electronics & Software
1

Hello

After several hours of looking for tricks to install my new usb - RS232 adaptater on w7 64b (I should have spend more time searching for infos instead of buying this random cable from Prolific), I finaly made it. Or it seems I did…
According to window’s device manager, everything’s ok and should work fine, but I can’t make it work with lynxTerm who return “Unable to open port com (win error code: 123)” when I clic on the “connect” button.

This is more likely to be a cable problem. I tried to link the rx and tx pins and sent chars via screen on Debian (after a dmesg check where everything seemed to be ok) and didn’t obtain anything.

I’m not really sure about what to do now. Any other idea than “Buy another adaptater” (I really think about it now.) ?

2

It seems like you’ve already done very thorough testing, and I can’t think of anything else to suggest.

We have the following USB-to-serial adapter that we’ve tested with Win7 and Win8 on 64 bit:

Hope this helps,

3

In the past I’ve used Prolific based USB serial adapters with lynxterm (maybe older version) with a ssc-32 on windows XP.

4

I still use one prolific adapter (One from Bafo) from time to time. Sometimes the difficulty is getting a valid driver installed. With my Bafo on some computers I found I had to run it using a powered USB hub to make it work. Note on those computers the usb connections on the computer was also supposed to supply power, but for whatever reason needed the external hub. I have also had some prolific based ones that would not work at higher speeds…

5

I tried the powered usb hub trick with no luck.
Losing a week because of a defective wire is anoying.

6

I think you can set one of the jumpers on the ssc-32 TTL pins so that what is sent from the pc is echoed back to the pc as a test of the USB serial adapter. Been a while since I’ve tinkered with the ssc-32.

7

I followed your advice and bought the adaptater. This is way better for sure, but still not enough. Maybe I’m missing something…
First of all, the conection problem on the w7 64b computer remains (error 123 on lynxterm). On the same computer the ssc32 recieved datas through Screen, so that’s ok for now.

I tried using lynxterm from another computer and with screen. In both case the led blinks when I send datas, I can get the version and I have a response to the "Q " command.
I followed zoomkat’s advice and I used a jumper to get my datas back : everything works fine.

Now here’s the problem : The servos do not move. I tried on several channels and with serveral commands (I didn’t forget the cr). I double checked the jumpers (2 verticals on rx and tx; all the jumper for vs1, vs2 and vl; and the jumpers for baudrate).

I wonder if it could come from the power supplied. As I currently have no other choices than 5.8V and 7.7V, I chosed to power the ssc32 with 5.8V but the user manual recommend 6V for the microcontroler to operate correctly.
Does it make a difference to use VS1, VS2 or VL (when all the jumpers are on) ?
Can I try to power the card with 7.7V (I read on the user manual to not apply more than 7.2V on servos, but also that the dropout regulator can take 9V) ? I’m using HS 485 servos.

EDIT : I sacrified a 9V power supply to make the test and it works fine.
Thank you for your help.

8

Great, we’re glad to hear you got it working!