Modem control line mandatory?

Hi all,

I try to connect ARM microcontroller to Huawei MC703 (CDMA EVDO), using Keil library.
If I connect using the PC (modem dial up) with RTS/CTS line used, connection is made and data transfer is OK. But if RTS/CTS line is not used, data transfer is not OK.

But if I use microcontroller, connection is made (received "CONNECT" message) but no subsequent data can be sent, even if RTS/CTS line is used.

Same firmware is used to connect with SIM900 GSM, and no problem found, RTS/CTS is not used.

My questions is:
- Does RTS/CTS line mandatory or make modem connection more reliable? I never use this control line before.
- Are there any difference in compression code, activation, security etc between CDMA and GSM?

Thank you for all members attention

Regards
Ojahan

Yes , compression code, activation, security are different for CDMA and GSM, In fact it more complicated in CDMA......
RTS and CTS are not required for GSM or CDMA(GSM type Modules) but formodules like EVDO it is necessary

Thank you for the quick response.

I wonder does the PC can automatically detect the modem(CDMA or GSM) it is connected to and use appropriate code.

Can you recommend me the CDMA modem (brand and model) that you already successfully connected with. I might need to change to another brand

Thank you
Ojahan

For PC we install drivers for that , EVDO and PC talk through those drivers..
I did not do it practically, but my students are doing it so doing some research on it.

I could do with CDMA modules same as GSM modules long back.....

---------- Post added at 18:14 ---------- Previous post was at 18:12 ----------

your application has tohave the information of the device signature, ID, name and number information, which you will get it in control panel of the device properties...

Hi thank you for the information,
I have checked again, whether there is driver used in the PC connection, and I can confirm no driver installed before, just normal PPP dial up
I think I need to analyze the PC <--> modem communication and emulate.