AT+WHWV
Hardware Version 4.23
AT+WOPEN=2
+WOPEN: 2, “AT v06.20”
i thought both suppose to give the same version?! 
Of course not:
AT+WHWV: Gives you the hardware version.
AT+WOPEN=2: Gives you the OS library version you used to generate you executable application.
Actually, if there is no application installed, AT+WOPEN=2 gives you the Open-AT OS version within the module firmware;
If an application is installed, AT+WOPEN=2 gives you the both the Open-AT OS version within the module firmware and the Open-AT OS library version you used to generate your executable application.
Note that the Open-AT OS version is not the same as the Firmware version, and neither of them is the same as the Hardware version - they are three distinct version numbers!
wow that’s quite confusing.
IMO the hardware version is not that important for compatibility,right? It is confusing b’cos the old Open AT OS also starts with number “4” and the older one is 4.23,same as the hardware version number (also 4.23).
With reference to WOPEN=2,for the embedded app to work both Internal and external version must be same, right?. But i have this code from company that can only works with OS 4.25 (b’cos of the GPIO) and my modem comes with OS 6.20, Firmware R73. Can something be done about it? Can i somehow perform downgrade? Would that effect other thing (WIP,etc)?
Sorry,so many questions!
*refering to WOPEN=2,there’s currently no embedded app on my modem yet,so i know why it gives only one version,but thanks awneil for explaining more.
Correct.
You already have a thread open on that subject: viewtopic.php?f=46&t=3654&p=14111#p14111
Don’t further confuse the issue by posting the same question in multiple places!
Sorry, i realize that. I just want to respect the rules by posting in the right section. I didn’t asked about the downgrade,effect to WIP,etc on the other thread b’cos that’s for GPIO-related thread. Here i didn’t focus on GPIO (sorry if that’s confusing,i just stated it in brackets in my question) but more towards OS and stuff so that i can reach the target readers. 
Is it possible to downgrade or it’s a big no-no?
*awneil how do you controll all the thread? u don’t have superpower,do you? kiddin’ :mrgreen: *
It is possible. However, as already noted, there were significant “breaking” changes between these versions; ie, they are not up- or downwards compatible.
Therefore the “downgrade” is not straightforward.
But, if I understand correctly, you have obtained these units specifically for use with this application - is that right?
Did you obtain the units from the same supplier as the application? If you did, they should have been supplied with the correct version; so your supplier is at fault, and your supplier should rememdy the situation - you should not interfere with the units!
If, on the other hand, you obtained the units from a different supplier from the application, and you omitted to specify the required version, I think you should just admit your mistake and ask them nicely if they will replace or “downgrade” the units for you. This will almost certainly be easier than trying to do it yourself and, therefore, cheaper - even if you have to pay to get it done.
I bought the modem from one of the supplier in germany. Since wavecom has co-operation with the company (the one that make the special IESM board i’m using) and the board is also mention in wavecom website, the supplier also sell the special IESM board. The company just provided me with documentation,code and some simple software, they don’t directly sell it, just like wavecom.
I think it’s partly my fault.
In my defence i did do the research before i ordered everything. For example i read the documentation for the IESM board beforehand and took notes all of the requirement for the board to work, such as FS 10 or 20 only,must be WIP enabled,sim card must be GPRS-enabled,etc. It did stated in the documentation that it only works for Open AT 4.23 OR HIGHER. At that time i am also quite blurry between the terms "Firmware"and “Open AT OS”. Since it stated “higher”, i assumed the newer one would also works.
i also has to fight with the time because it could take weeks to arrive.
Gosh, besides the help from this forum, both contact person from supplier and the company have not replied yet! Usually they are very quick. I hope they don’t go to vacation or something since summer is just starting here and the weather is warm and sunny since last week!!(and i’m stuck here in my office! 
)