EHS5 module start up time | Telit Cinterion IoT Developer Community
August 11, 2014 - 9:52pm, 3512 views
I've observed the EHS5-US take around 30 seconds from initiating a power-on to it issuing the +PBReady and being capable of establishing a data connection.
Questions:
1. Is this time typical?
2. What precisely is the module doing during this time?
3. Are there tradeoffs to be made or strategies to minimize this startup time? Our application is very power-conscious so we would ideally keep the module off most of the time (as opposed to in a sleep state), but are curious if there are optimizations that we could be making.
Thank you
Aug 12 2014 - 1:53pm
Hello,
Ad.1. This is typical, but please consider Ad.2.
Ad.2. Module initialization includes starting Java and performing SIM readouts. Old and cheap SIM cards provide lower non-volatile SIM data reading performance. Due to that they can significantly limit SIM interface transmission speed. I've checked it on my desk - for one card the module sends +PBREADY after 20 seconds, for another after 27 seconds.
Ad.3. Unfortunately there are no special procedures to speed up initialization procedure. I would recommend to change SIM card for faster one as the cards you're using seems to be quite slow.
Regards
Jedrzej
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Aug 12 2014 - 9:19pm
Thank you so much for your answers and your quick response.
We will look into better performing SIM cards.
One clarification on the java initialization side of things though: we are sending AT commands directly to the EHS5 through the USART (from a microcontroller), and aren't writing any sort of program that lives onboard the EHS5. Is the java initialization still strictly necessary for our use case? ie, does java drive the AT command interpreter as well as any programmed behavior? I was wondering if we could somehow short circuit this step if in fact we weren't actually utilizing it.
Thanks again!
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Aug 13 2014 - 1:39pm
Hi,
some of module's features are implemented in Java. JRC midlet that you can see when listing working midlets using AT^SJAM=5 controls part of module's functionality. It is strictly recommended not to touch it as the module will not work properly. Besides, even if JRC is disabled, Java Virtual Machine will be started, so time saving wouldn't be noticable.
Regards
Jedrzej
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