SL6087 firmware upgrade with xmodem and USB


I have to upgrade the firmware of our SL6087 modems.

I understood that I can do it using the RS232 link and the xmodem protocol.

Statement found from here: … D=&aid=487

It would be much more convenient for me to use instead the USB link for various reasons. This link is enabled with AT+WMFM=0,1,3

Question 1: is the upgrade possible using the USB link ?
Question 2: is there any specification regarding the upgrade ?

Thank you.

Yes it is possible.
Once you install the proper USB driver for SL6087, you can see the AT port from the ‘Device manager’. Select this port when you are selecting the port in the hyper terminal. After that the procedure is same :slight_smile:


Thank you Alex,

I’ve just made again the test with Linux (no “Device manager”). I’m able to send a file by xmodem when I’m lucky. The USB link is very unstable as soon as the AT+WDWL command is sent. In a first step, the USB device disappears, then comes up after some seconds. Then its associated serial link (tty in Linux) is claimed to be busy during some seconds. Finally I have access. At this stage, I may receive nothing or receive NAK (success !) or receive AT responses from the modem. Something really weird like ATV1 AT+CMEE=1ATX4 AT&C1 etc… since I’ve not sent any command like that. Note that I’m confident in the physical layer of the USB link since it i’s used with success for a PPP connection.

I’m trying to upgrade the firmware R7.44 to 7.52.

Now I’m wondering if the Linux sytem is not calling automaticaly somekind of modem manager once the ACM link goes up… That could cause my troubles.

Now that’s much better.

My Ubuntu ModemManager was starting automatically thanks to the udev rules. This app was confusing my xmodem of course. For the ones who read this, here is the procedure in Linux :

  1. ensure that no modem application will be launched when an ACM USB link appears. Add for example this file :
    Content :
    ATTRS{idVendor}==“114f” ATTRS{idProduct}==“1000”, ENV{ID_MM_DEVICE_IGNORE}=“1”

Take this modification into account, reboot or sudo udevadm control --reload-rules

  1. Follow instructions from … D=&aid=487
    But, when “AT+WDWL” is sent, the tty must be closed, then wait a couple of seconds, and try to open the tty serial again until the device comes up. It take around 20 seconds. Then the NAK characters can be seen.


Yes, this is because your modem is getting ready to download…