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Old Aug 14, 2009, 02:22 PM
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We have the Problem that the receivers are not working correct or jittering as hell, depending from which BEC(ESC) they are driven. The problems never occour if we use a normal receiver battery instead of the BEC. The same BEC(ESC) works without problems with my other 35MHz, 27MHz and Assan receivers. Allthough on other BECs the same receiver works flawlessly... Anyone experienced the same problems?
I remember this happening with other receivers, not just the Turborix ones. It is usually a sensitivity to the ESC and BEC generating some noise on the power and signal lines or too low of a voltage as well. Sometimes putting in filters to help block the noise works. This is like hooking up a 220ufd capacitor on the +/- wires from the ESC throttle pigtail. Sometimes you have to put in a small inductor and a couple .01ufd caps on the +/- wires too. The EXC's typically generate a high frequency PWM signal for the motor and the RF noise from the ESC can backflow into the receiver.
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Old Aug 14, 2009, 03:55 PM
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Quote:
Originally Posted by ReSt
Satellite receiver disconnected.
Pictures taken on one of the solder pins, where the rf board of the main receiver is wired to the mainboard of the main receiver.

(Datastream at the external plug of the satellite to the main receiver visually looked the same).

Reinhard
Thanks very much. One more question:
Quote:
Originally Posted by ReSt
A bit is about 24usec long resulting in a datarate of about 41.66 kBd.
One-bits are negative, zero-bits positive level. There is no duration between bits.
As long as the level is negative, there are one-bits (no return to zero).

I have counted one measured bitstream up to and including channel 5.
(It looked like there were 9 blocks, the first 6 blocks having data for 6 channels, the last block maybe a checksum. But I don't know what is in between.)

There (thanks vince29) I could see:

Single Channel data start with one startbit (-) followed by 16 databits followed by 5 stopbits (+) followed by the next single channel data according to this scheme.
The 16 databits come with least significant bit (LSB) first. Reverse the bit sequence. Subtract this value from 65536. That is the timing value of one channel in usec.

Example stream:
10111010100011111000001011111111001111100000101101 0101101111100000.......

.1011101010001111100000 first 22 bits (1S,16D,5Stp)
. 0111010100011111 16 databits LSB first
. 1111100010101110 bitsequence reversed (MSB first)
. 1111 1000 1010 1110 Hex F8AE -> dec 63662
65536 - 63662 = 1874 length of channel pulse = 1874usec =1.874msec
If 'A bit is about 24usec long' and there are '22 bits per channel' shouldn't the length of a channel be 24 * 22 = 528 usec or .528 msec instead of 1.874 msec?
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Old Aug 14, 2009, 04:26 PM
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Quote:
Originally Posted by CitizenKane
Thanks very much. One more question:


If 'A bit is about 24usec long' and there are '22 bits per channel' shouldn't the length of a channel be 24 * 22 = 528 usec or .528 msec instead of 1.874 msec?
No, the 1.874 is the value that is encoded in the bits. Because the radio is modular, is uses an intermediary of ppm encoding. In the receiver this value is sent to the servo with the length of a pulse again.
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Old Aug 14, 2009, 04:33 PM
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Quote:
Originally Posted by JelleB
No, the 1.874 is the value that is encoded in the bits. Because the radio is modular, is uses an intermediary of ppm encoding. In the receiver this value is sent to the servo with the length of a pulse again.
Superb - thank you very much!
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Old Aug 14, 2009, 04:37 PM
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Quote:
Originally Posted by CitizenKane
Thanks very much. One more question:


If 'A bit is about 24usec long' and there are '22 bits per channel' shouldn't the length of a channel be 24 * 22 = 528 usec or .528 msec instead of 1.874 msec?
As JelleB already explained, 1.874msec is the decoded content of the 22 bits.

The .528msec you calculated is the time it needs, to transfer these 22 bits.

Reinhard
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Old Aug 14, 2009, 06:08 PM
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The pictures show the datastream that the main receiver sends once to the satellite receiver (with disconnected satellite receiver) at power on of the receiver.

Reconnecting the satellite receiver while power stays on, will not bring the satellite receiver online again.
Powering off and on the receivers brings both receivers online again (without another binding process).


These are my assumptions and findings from measuring the timings as good as possible.

First Picture shows the full datastream consisting of 9 bytes (1 start bit, 8 data bits, 1 stop bit). The inactive high level between two bytes is 610 usec long (stop bit + delay).

The datarate is the same as for the channeldata, about 41.66kbd

Supposed, the low level (the active one) means a 1-bit, and that the least significant bit comes first, the databytes have the following values:

1E A3 FF FF AA AA AA AA AA

I don't know, what these bytes represent, but I know, that the satellite receiver does need them to go online.

Reinhard

[edit]
As we agreed, that high level means a 1-bit and low level a 0-bit, the data then is:

E1 5C 00 00 55 55


Second picture has an error. In the picture, the delay between the bytes is stated as 610 msec. This is wrong, it should say 610usec as stated in the text above
[/edit]
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Old Aug 14, 2009, 06:14 PM
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someone already built a training cord for HK-T4A?
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Old Aug 15, 2009, 12:25 AM
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Quote:
Originally Posted by (Jo)Hannes
We have the Problem that the receivers are not working correct or jittering as hell, depending from which BEC(ESC) they are driven. The problems never occour if we use a normal receiver battery instead of the BEC. The same BEC(ESC) works without problems with my other 35MHz, 27MHz and Assan receivers. Allthough on other BECs the same receiver works flawlessly...

Anyone experienced the same problems?

try re positioning the rx's
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Old Aug 15, 2009, 12:43 AM
Heli Humbled Daily
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Joined Jul 2006
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Sony Clie Working

Thanks To ReSt's great PDA program, and some help with my circuit, I have successfully gotten my old Sony Clie S320 to work programming the Flysky 6 channel radio.

Using data from this site:

http://euroclie.free.fr/Uk/cable.html

the Clie's serial port is activated by using a 50k ohm resister to drop the voltage to pin number 2 to 1 volt. Then it follows the diagram ReSt gave us around page 80, only I bread boarded the project with a Max232 clone I had in my stash (gotta use 1uF caps with the original Max232) and it seems to handle the data transfer just fine.

If I setup a model memory in the Palm, it saves and loads fine, and the checksum on startup is fine.

Howver, if I load i config file from T6config, and then plug the controller into the Palm program, it says "Checksum failed" every time. Will the palm program not read all the settings setup by T6config?
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Old Aug 15, 2009, 07:10 AM
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Quote:
Originally Posted by Telemachus
Howver, if I load i config file from T6config,

you load the configuration from T6config program into the transmitter ?

Quote:
and then plug the controller into the Palm program,
do you connect the transmitter with the PalmTx program already running ?


Quote:
it says "Checksum failed" every time.
on which of the panels are you and what did you do to get this message ?

This normally means, that there was a receive error within the data, the palm received from the Tx.
The transmitter sends the configuration data confirmed by a two byte checksum. If the checksum that the Palm calculates differs from the checksum that the transmitter appended to the data, you will get this message.
But it means, that the Palm could read some of the data, or you had gotten the "Tx not connected?" timeout.

Maybe that this is the problem with the Max232 (not Max232A) running near its maximum transmission speed.
While channel data is a string of only 18 bytes, configuration data is 69 bytes long. So configuration data is much more error prone than channel data.

When the Palm sends a configuration to the Tx, the configuration is not read back and verified. The Tx will simply not use it, when he gets a checksum error.

Quote:
Will the palm program not read all the settings setup by T6config?
The program reads the actual configuration of the transmitter when it is started to display the "Overview" screen and when you leave this screen. The "Cfg" switch in the top line should be white letters on dark background to indicate, that the configuration from the transmitter has been read successfully.

Tapping on the Cfg switch will try to reread the configuration from the transmitter into the palm when on the overview screen.

Tapping on the Cfg switch on the other panels will try to send the actual configuration of the Palm to the transmitter.

Reinhard
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Old Aug 15, 2009, 09:17 AM
Heli Humbled Daily
Riverside, CA
Joined Jul 2006
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I thought that perhaps the Max232 was the issue. I'll have to track down a 232a somewhere. However, if I set up the controller all within the palm program, it will read the config just fine on the home screen. I have set up several models only in the palm, and it reads all those configs fine. Only if I setup the controller in t6config and then try to hit CFg In the palm does it fail checksum...
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Old Aug 15, 2009, 10:57 AM
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Quote:
Originally Posted by Telemachus
I thought that perhaps the Max232 was the issue. I'll have to track down a 232a somewhere.
if all else fails you can buy small quantities or get samples of maxim stuff direct from them. no outrageous mins or fees

www.maxin-ic.com


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Old Aug 15, 2009, 11:53 AM
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Quote:
Originally Posted by Telemachus
and then try to hit CFg In the palm does it fail checksum...
Why do you hit the Cfg key ? and on which panel ?

If you start the program, before it displays the 'Overview' screen, it will automatically read the configuration of the Tx.

Reinhard
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Old Aug 15, 2009, 01:28 PM
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Pacifica, CA USA
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I installed the drivers and t6 config but my transmitter doesn't communicate with my pc. I can see and select the right com port number but the t6 config will freeze. I have to turn off the receiver to make changes again. When I move the joystick, it doesn't do anything on the config screen like on the youtube video.

WinXP Pro SP2
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Last edited by norstaroption; Aug 15, 2009 at 04:16 PM.
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Old Aug 15, 2009, 02:20 PM
Time for another motto!
Utrecht, The Netherlands
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Quote:
Originally Posted by ReSt
Reconnecting the satellite receiver while power stays on, will not bring the satellite receiver online again.
Powering off and on the receivers brings both receivers online again (without another binding process).
That may be because the satellite goes into binding mode when no frequency info is coming from the mainboard, I think. I have seen the first part, the freq info is educated guess.
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