DSM2 transmitter attached to Arduino via RS-232

This is a big challenge.  Please review the MAX232 IC data sheet and see if you can manage it.

Do a search using Google and YouTube for MAX232 and Arduino.  I think you may find what you need.

Happy Trails.

Ha.  The OP caught me shooting from the hip and missing the target completely.  Good call, OP.

Hey Bill!

I want my computer to connect to the Arduino via a USB cable, only for the sake of uploading the code and the Tx1-K1 DSM2 transmitter to connect to the Arduino, using the Arduino  TX and PWM pins using the RS232 protocol.

I think there is no need in this project to connect the Arduino directly to the computer using the RS232 protocol or RS232 hardware.

Have i misunderstood anything?

Thanks a lot,

Roi.

Let's see there are two distict features that make up RS-232 specification.  One is the well known 8-N-1 at a given baud rate which is 115200 according to the data sheet pdf you provided the link to.  And then there is the electrical signal level for which binary 0 is -8 V and binary 1 is +8 V.

Your TX does not seem to work with true RS-232 signals.  Having located and read a document from the OEM's website, I have come to the conclusion that you REALLY need to read it too.  Especially, Section 4 which shows how to feed pin 7 (or 8).  http://www.deltang.co.uk/tx1-112.htm  This MAY NOT be the correct document for your TX.  If that is the case then please do tell me which is the right one.  Pay attention to the power supply requirements and there will be no tears because the TX got tore up.  Since the Uno is 5 V on a high (binary 1) you REALLY must understand and follow what the OEM shows about the interface between the Uno's output pin and pin 7 (or 8) of the TX.  Again, I point you to Section 4.

I don't know but the answer you are looking for may be how to create and send the PPM signals into pin 7 (or 8) of the TX.  For that, I refer you to the Arduino Forum.  http://forum.arduino.cc/index.php?PHPSESSID=g7vue61elc4pk3312kt7uvrtl6&topic=146982.0  ,  http://forum.arduino.cc/index.php?PHPSESSID=g7vue61elc4pk3312kt7uvrtl6&topic=146982.0 and other discussions posted there that may be easily be found by inputting "ppm tx rc" into the search box on the Arduino Forum's pages.  Where you might learn that PPM is only between the TX and RX.  Ha, gotcha!

Does your difficulty lie with creating, maintaining, and TXing a required 16 byte array?

Byte 1 Checksum (sum of bytes 2-16 cast to 1 byte)

Byte 2 Not used (can be any value)

Bytes 3-16 2 bytes per channel with following structure 0b000 CCC PPPPPPPPPP    for a total of 16 bits which is 2 bytes

- 000 = not used (normally zeros)

- CCC = channel number (0b000=Thr, 0b001=Ail, 0b010=Ele, 0b011=Rud, 0b100=Gear, 0b101=Aux1, 0b110=Aux2)

- PPPPPPPPPP = 0b0000000000 <= 10bit channel position <=0b1111111111

Happy Trails

billabott wrote: And then there is the electrical signal level for which binary 0 is -8 V and binary 1 is +8 V.

The actual RS232 specification for logic levels is binary 0 is minimum of -3V (maximum is -15V) and binary 1 is minimum of +3V (maximum is +15V).

Many RS232 recievers will accept  0 V as a binary 0 although this is clearly out of spec.

Thanks, Gary.  I was just quoting something (dated) I read the other day.  Wikipedia is my friend, too.

William is quite right.

You can indeed send data out of an Arduino to this device, which may in turn communicate with the Rx.

So to answer your question.

Get some wires and connect to pin 7.

If you want a sketch then I'm afraid there is much more information required.

ie, how are you going to provide the input information, how many channels, which input on the Arduino is what, etc.

Mark

Hello Mark!

I would definitely need a sketch, since i have little experience in hardware and software.

I am even having trouble understanding all the 16 bytes, 10 bit, checksum, CCC, 00011111 stuff - If i had a sketch and a wiring diagram, that i can copy and paste the code and upload it (both i already have, but it doesn't work up to this moment) and then successfully the receiver and transmitter would bind and if even one servo moves in a predefined way - then i can start playing with these 0001111 arrays and try to understand how these bytes and bits influence the servos reactions. i understand the basic concept of binary counting, but not much more.

My final goal in this project is to have 4-6 servos connected to that receiver - using all the channels it is? i will need quite an elaborate animated synchronized movement sequence of these servos. Is there no way to record with joystick ot mouse a sequence of movements and automatically 'translate' these movements to the 0's and 1's language?

Otherwise, would there be a need to manually insert a long list of these bytes in the code?

If there is still more information that i can provide to enable you to help me, please let me know.

Thanks,

Roi.

Roi

Sorry I have enough to do for myself without writing code for other people.

The forums are to help, however someone may take pity on you.

You have some code, so maybe posting that will show where you're going wrong/right.

I presume there is basically a 'start' button, and then the various servos move in a preconfigured manner.

You will need to be storing this for each of the 'servos' and sending it out.

The reference to 10 bit is a number from 0-1023 (which in binary is 10 bits).

So effectively if you send it 512 (in binary) it should translate to mid position on the servo.

How you capture or work it out, is your next move.

Mark

Roi

Sorry I have enough to do for myself without writing code for other people.

The forums are to help, however someone may take pity on you.

You have some code, so maybe posting that will show where you're going wrong/right.

I presume there is basically a 'start' button, and then the various servos move in a preconfigured manner.

You will need to be storing this for each of the 'servos' and sending it out.

The reference to 10 bit is a number from 0-1023 (which in binary is 10 bits).

So effectively if you send it 512 (in binary) it should translate to mid position on the servo.

How you capture or work it out, is your next move.

Mark

Hey Mark,

Thanks for replying.

Cheers,

Roi..