Problematic behavior of GPIO4 in the EHS5 | Telit Cinterion IoT Developer Community
April 3, 2019 - 12:01pm, 3008 views
Hello,
After powering the EHS5, GPIO4 is HI and after 1 second goes LOW.
It occurs in Rev3. Not in Rev2.
This is problematic because I use this pin for hardware reset trigger, and I need Rev 3
Is there any solution to change that GPIO4 behavior?
Hello,
This line is shared between GPIO4 and fast shutdown functionality which both are mutually exclusive. However this design is the same for revision 2 and 3. Please check AT^SCFG? output to verify if the line is configured properly. Please also send ATI1 reply. Is any hardware connected to this line while you make the test? It might also be possible that this hardware is causing such problems. Was the design changed?
Best regards,
Bartłomiej
Thanks for reply.
I unconnected any external hardware from GPIO4 for test.
The GPIO4 still goes LOW after second from powering.
Rel2 and Rel3 behave different on the same EHS5.
Rel2 is OK, Rel3 not.
Hello,
Are you going to use rev3 modules for your project? Currently we have revision 4. I'd suggest you to contact your local technical sales.
I've tried this on rev3 and I've also seen a line toggling on start. For now I can't see a way to get rid of this behavior. But I don't see this toggling on rev4. If you're going to use rev3, you can choose some other GPIO line if it is possible for you.
I can see that this problem was also reported to the support line. Please also keep track on it there.
Best regards,
Bartłomiej
Thanks for your help.
We reported this problem to the support line but this problem was not resolved, so I decided write about this here.
I can't change GPIO line because we have a lot of manufactured modems.
Changing revision is also very problematic for us.
Regards
Hello,
Revision 4 requires the new hardware so it is not the option if already have the devices and modules.
As for the support line the problem is analyzed - if you have access to SF, please write any question or additional information that might be helpful. Or please ask your TS if you don't have a direct access.
Regards,
Bartłomiej