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Old Nov 23, 2012, 06:17 AM
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If you want to improve the Devo 7 transmitter. I don't know the capabilities of the main board and microcontroller included in the transmitter, but you said that this microcontroller is very limited. If this is true and is not capable to support a good screen or your new firmware, then the option is to substitute the main board by a generic main board with more capabilities but it has some disadvantages because you need to make many solderings, etc. Probably you should need to make the design of a new board, and this probably is out of the scope.

The best solution is to maintain the old main board with the old microcontroller and add a new generic board with a powerfull microcontroller and a good sized screen. You should reprogram the old microcontroller so it only deals with the inputs, potentiometers, switches, trims, sticks, etc, and it will deal with the RF module as a transparent module for the new microcontroller. The old and the new microcontroller communicates trough the old wires used in the old screen.

You should implement an easy protocol to comunicate the two microcontrollers so the new microcontroller can ask for the inputs and send the output for the RF module by connecting with the old microcontroller. It is not difficult to adapt your firmware to do that, and no much more wires are required. The power on/off could be managed in a similar way. It notifies to the new microcontroller the intention of power off, and the new microcontroller notifies to the old microcontroller when all is ready.

By proceeding on this way (the new microcontroller makes all the work and the old microcontroller only deals with the inputs/outputs), you can support telemetry, or make a transmitter as many powerful as you could want.
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Old Nov 23, 2012, 07:49 AM
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Originally Posted by PhracturedBlue View Post
Search aliexpress or ebay for "a7105 500m". That is the module you want. You can find a pic of it (and a link that may not be good) in the Flysky conversion doc
Thank you! I have ordered it and now the waiting part
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Old Nov 23, 2012, 09:25 AM
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Quote:
Originally Posted by Tripert View Post
By proceeding on this way (the new microcontroller makes all the work and the old microcontroller only deals with the inputs/outputs), you can support telemetry, or make a transmitter as many powerful as you could want.
You are right that is would be easier, though it wold mean hat conversion of the 2603/2801 would not be possible. It would probably work fine for the inputs, but I can't see how to get the necessary accuracy for driving the radio. Still, the radio module is removable, and could be easily wired to the new board with only 6 pins.

I like the STM32F103VET6 boards. they would be a drop-in replacement for the current code which runs on a STM32F103VCT6 (exactly the same but with less RAM/Flash). You can find the same 2.4" board you listed for $40 shipped, which is still reasonable for a conversion I think. There are also some standalone boards without display available in the $20 range. I'm looking into these more now.

I already have an F103RBT6 board. It has 2 issues: 1) the number of free I/O is too small (they are all used by the board) 2) It will be difficult to get the current code small enough to fit in memory. However, the 7E apparently uses this chip, so getting the code to fit here will eventually be needed to support the 7e

I also have a teensy, which is really nice and small. it has lots of free I/O, but has the same memory limitations of the F103RB. It also has no off-board memory which means we need a tft with flash/SD.
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Old Nov 23, 2012, 09:34 AM
Mini CP - Nano CPX - Devo 6
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United States, CA, Laguna Niguel
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Can anyone confirm the connectors on the Devo modules? It looks like a U.FL connector going to an SMA or an rSMA. I'm looking to replace that part and I'm not sure what to get, I have the original Devo 8 antenna and module but need the part in between.
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Old Nov 23, 2012, 11:20 AM
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FDR's devo page lists this as the mono-display used by the devo10:
http://www.tinsharp.com/detail/&prod...189735664.html
which looks right, but I can't seem to find a supplier that would sell in reasonable quantities.
It quotes the visible area as: 66mmx38mm

The 2.4" module on the F103VET6 has a visual area of 37mm x 50mm so it should fit nicely in the window (with some black space).

So, I'll likely try a few things:
2.4" screen:
http://www.ebay.com/itm/2-4-inch-TFT...item564efb75a7

2.4" with F103VET6:
http://www.ebay.com/itm/STM32-STM32F...item255e52ffcc

F103VET6 without LCD:
http://www.ebay.com/itm/STM32-Develo...item3a6895caf9

some combination of those along with my teensy3.0 should provide a suitable platform for development.

Of course they are all coming from china, so it'll like be a month before I can even start
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Old Nov 23, 2012, 12:13 PM
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The election is not easy.

It likes me more because it has touch screen.

2.4'' STM32F103VET6
http://www.ebay.com/itm/ARM-Cortex-M...item1c2a2fe129

But a good election could be to select a device that could be programmed by using bootloader (by USB) without a special programming device.
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Old Nov 23, 2012, 01:20 PM
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Quote:
Originally Posted by Tripert View Post
The election is not easy.

It likes me more because it has touch screen.

2.4'' STM32F103VET6
http://www.ebay.com/itm/ARM-Cortex-M...item1c2a2fe129
That is the same board I listed but at much higher cost.
Both LCD panels I listed are touch aware.
All STM32 boards with a USB port can be programmed with USB (though most will need initial programming via serial to install the bootloader)
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Old Nov 24, 2012, 03:55 AM
...muy bien...
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Germany, BW, Pforzheim
Joined Jul 2012
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UDIRC u816 / u817

Anybody knows if the Devo can control those quads?

Unfortunately I can't tell if other non Udi radios are compatible. Could be a 9x derivate...

Here is a link to the QC I am talking about
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Old Nov 24, 2012, 09:58 AM
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Originally Posted by rcgchris View Post
Anybody knows if the Devo can control those quads?

Unfortunately I can't tell if other non Udi radios are compatible. Could be a 9x derivate...

Here is a link to the QC I am talking about
the tx looks a lot like the v911s. If they used the same board, it probably supports the 9x protocol. But without someone trying it, there isn't much way to know.
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Old Nov 25, 2012, 03:48 AM
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I have the u816 sometimes back and tested with deviation and nope its not working. And that's before my v911 module had any issue.
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Old Nov 25, 2012, 07:20 AM
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Originally Posted by OnceAFly View Post
I have the u816 sometimes back and tested with deviation and nope its not working. And that's before my v911 module had any issue.
Well, if you open up the tx or rx and take some detailed pics of the board, it would tell me whatthe options are. If it is a7105 based, I'll grab one and work on the protocol.
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Old Nov 25, 2012, 07:33 PM
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Here are some of the photo from tx.



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Old Nov 25, 2012, 07:49 PM
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well. they have a blob of epoxy over the transceiver chip which makes it pretty hard to know anything without scraping it off. Is the receiver any better?
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Old Nov 25, 2012, 07:51 PM
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Also, is there any chance that the Tx has an FCC code on it, or in the manual? We could look up the FCC docs, and see if it helps (though they may have asked for them to be classified, so it isn't a sure thing)
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Old Nov 25, 2012, 09:43 PM
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Well, from this image of the Rx:
http://i01.i.aliimg.com/img/pb/525/8...842525_839.jpg
I can deduce:
It is very unlikely to be an A7105. the Xtal pins on the a7105 are clockwise to the PSI pins, but are CCW in that image

It is very unlikely to be a CYRF6936 The xtal is connected opposite the SPI bus on the CYRF6936.

It is possibly a CC2500, but I think it unlikely due to how the bus is routed from the MCU to the transceiver

It is likely to be an nrf24l01. The pins I can see from an (albeit very fuzzy) picture seem to correspond best to this option
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