EHS6T USB undervoltage reset? | Telit Cinterion IoT Developer Community
November 19, 2015 - 2:25pm, 2665 views
Hi,
Is there any way to reset the terminal, if the voltage on the USB bus falls too low (2...3V)?
The ADC could be used to measure this but is there a better way.
Antero Markkula
Communication and Mechatronics
Enkom Active Oy – www.enkom-active.fi
Upseerinkatu 3 A, 02600 Espoo, Finland
Mobile: +358 400 411368
Office: +358 10 204 0000
Fax: +358 10 204 0010
E-mail: antero.markkula@enkom-active.fi
Hello,
There's no such functionality. There's only undevoltage or overvoltage alarm URC's and shutdown for supply voltage. Ot the command to read supply voltage.
So you'd need to use ADC and implement some reset.
Could you write what could be the reason for that?
Regards,
Bartłomiej
Customer has found USB enumeration issues if the connected USB device loses power.
They would like to detect this from the USB and issue a reset to EHS6T USB if necessary to keep the USB connection alive.
Antero Markkula
Communication and Mechatronics
Enkom Active Oy – www.enkom-active.fi
Upseerinkatu 3 A, 02600 Espoo, Finland
Mobile: +358 400 411368
Office: +358 10 204 0000
Fax: +358 10 204 0010
E-mail: antero.markkula@enkom-active.fi
Hello,
Thank you for additional information.
So it doesn't need to be USB, it could be even some other line to monitor via ADC or GPIO. Or there could be some keep-alive mechanism implemented in the communication protocol on USB.
Regards,
Bartłomiej
Hi Antero and Bart:
I'm having also that problem. I'm using ehs6 with an embedded linux board, as a modem. And when i call or recieve a call, ehs6 resets, and USB acts as if you have unplugged and plugged again. I triple checked supply problems, and Vbat never gets under Vbat-0.4V, as datasheet says.
Have you solved this issue? Do you know if this happen using ASC0 instead of USB? Is a known bug?
Thanks both in advance.
Hello Arturo,
Your problem looks different - it is not the device connected on USB but the module itself that resets in your case.
Current consumption during the active call is much higher than in the idle **** so it could still be the power supply problem.
Please check the details in the hardware description.
Regards,
Bartłomiej
Hi Arturo,
Do you have more devices with this problem or only one?
It would be the best to compare if this also happens on the developer board or some other hardware.
The hardware seems to be the most probable cause but we cannot exclude others.
Please provide ATI1 reply to check the firmware version.
Regards,
Bartłomiej