MAX232EPE and RS232

Projects Interfacing w/ Software on the Computer
1

Hi, I just have Siemens TC35/MAX232EPE -arduino board. I have problem get connect using RS232-cable and hyperterminal.
This are my settings:
Bits per second: 19200
Data bits: 8
Parity: None
Stop bits: 1
Flow control: None

Everyting else is default settings.

When I write at there should come answer ok, but theres nothing.

If someone can help me, please?

2

Sure, post your sketch.

3

I have just buy this board and getting study it. First I'm trying to get ok response the at command, like this youtube clip: devpacific 2.0: TC35 GSM SMS Demo Video - YouTube.

I think theres some mistake my hyperterminal -settings. Or could there be someting else?

4
  1. Have you got the datasheet? I couldn't work my way through the Chinese stuff which seemed to be asking me for a password.
  2. Have you applied the correct DC power to the board? It's extremely unlikely that it is powered from the RS-232.
  3. Have you got the right kind of RS-232 cable?

Pete

5

Yes I have datasheet, and there's some settings about using RS-232. Cable must be basic, not Zero-Modem -cable. I have use two kind of cable RS-232 - RS-232 and USB - RS-232.

I cant get any password question and DC power is correct 5V.

When I use SIM -card it's sound alarm when calling.

6

There are 2 kinds of RS232 cable:
This kind is sort of like Master talking to Slave,
Output on Master 2 is Input on Slave 2, and
Inout on Master 2 is Output from Slave 2
5 is Ground.
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and this kind is more like 2 masters talking to each other.
Master1 output on 2 goes to Master 2 input on 3,
Master1 input on 3 comes from Master2 output on 2.
5 is ground.
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If you look up RS232 DTE and DCE (Data Terminal Equipment, Data Comminication Equipment) you will see the difference.
You can determine which cable you have with a multimeter.
You will need to check the manuals to see which is needed for the items you have.