Serial communication

Hi all.
I have arduino UNO board and connect it whit RS232 cable with PC.
Comm. parameters 9600,8,n,1.

This code on arduino:
Serial.print(‘M’);
prints Y character on PC side. Why not ‘M’???

(deleted)

Yes, thanks a lot.
I must connect RS232 TTL converter.
LOL

I put RS232-TTL converter and still have the same result?

Hmmmm...How?

(deleted)

Yes, on both sides I use 9600,8,N,1.

I'm not sure what is the problem.
arduino RS232-TTL
3V3 ----------VCC
Tx-------------TX
RX-------------RX
GND-----------GND

Please, tell us which way of the following you have followed to connect your UNO with PC?

1. This cable arduionoConnectingCable.jpg (that comes with UNO) to connect between J1 of UNO and an USB Port of PC.
unoBoard.jpg

2. If not the above one, then show the connection diagram.

unoBoard.jpg

arduionoConnectingCable.jpg

Hi, thanks all for help.

One end is connected to RS232-TTL and another is connected to USB-RS232 converter. On both sides is DB9 connector.
RS232-TTL converter is wired to arduino as mentioned above.

Tx-------------TX
RX-------------RX

Wrong

schomke:
One end is connected to RS232-TTL and another is connected to USB-RS232 converter. On both sides is DB9 connector.
RS232-TTL converter is wired to arduino as mentioned above.

There is serious communication gap between us. I am not getting answer to my question, which means that you have not understood my query of Post#6.

I tried also to change rx, tx order.
Sorry, i'm not use that blue cable. I use another one with same communication ports.
I hope that I answer what you ask...

schomke:
Sorry, i'm not use that blue cable. I use another one with same communication ports.

Are you connecting one end of that cable with J1 connector of UNO (Fig-1)? If so, then do you know that signals at J1 are USB? If possible, please give a link to that special cable?
unoBoard.jpg
Figure-1:

unoBoard.jpg

Yes. It's conncted to J1. From PC USB port, cable goes to J1. I use that connection only for programming. That cable is typical printer cable.
Second connection to PC is, as described in earlier posts.

Yes. It's connected to J1. From PC USB port, cable goes to J1. I use that connection only for programming. That cable is typical printer cable.
Second connection to PC is, as described in earlier posts.

OK, so, are you trying to get the ttl serial i/o from Arduino pins 0 and 1, and you connecting those pins to a TTL to RS232 converter?

One end is connected to RS232-TTL and another is connected to USB-RS232 converter. On both sides is DB9 connector.

If you are trying to get a second USB serial port between the computer and the Arduino, why are you going through RS232 instead of using a TTL to USB converter between the Arduino and the PC.

Post the codes (with code tags) that you have uploaded into UNO.

cattledog:
OK, so, are you trying to get the ttl serial i/o from Arduino pins 0 and 1, and you connecting those pins to a TTL to RS232 converter?

Yes, that's right.

If you are trying to get a second USB serial port between the computer and the Arduino, why are you going through RS232 instead of using a TTL to USB converter between the Arduino and the PC.

This is just test. I should to connect arduino with some touch panel which have rs232 db9 port.

GolamMostafa:
Post the codes (with code tags) that you have uploaded into UNO.

Code is simple:
void setup(){
Serial.begin(9600, SERIAL_8N1);
}
void loop(){
Serial.print('M');
// Serial.write('M');
delay(1000);
}

With the two converters and the DB9 cable there are many ways for the RX/TX connections to get in the wrong configuration. You will need to provide much more documentation on the converters , the cabling and how you have it all connected. Some DB9 cables/connectors have RX/TX crossovers and some do not. You have a reasonably complex situation to sort out to be certain that the TTL TX from the Arduino is actually getting to the USB RX.

To help trouble shoot, do you have a scope to look at signals?

schomke:
I have arduino UNO board and connect it whit RS232 cable with PC.

Still, I could not get how you have connected your UNO with PC.

Please, show your connection diagram.

Attached is handwriting wiring diagram.
Aslo I tried, after uploading the program to disconnect programming cable USB.
Start Terminal program on PC and watch receiving telegrams.