Espritmodel.com Telemetry Radio
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Old Aug 15, 2012, 04:30 PM
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Try with a P-MOSFET (AO3401 for example). It ran fine for me. It is easy to find at Ebay.
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Old Aug 15, 2012, 04:45 PM
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Originally Posted by Tripert View Post
Try with a P-MOSFET (AO3401 for example). It ran fine for me. It is easy to find at Ebay.
Yes...I'm the one who advised you what the best options were. But you need to work with what you've got at hand, and I didn't have any 5V FETs. The nice thing about BJTs is that they have much wider range of voltage support, so it is easier to patch something together. Since my system is working as is, I'll probably live with it. The flickering is not visible during regular use, only during programming.

EDIT: For reference, the Devo8 seems to peak at about 1.5Watt total power draw. that's measured from the charging jack (without the battery plugged in). I expect the draw to be less with the battery pack since the 5V->3.3V conversion is more efficient than 10V->3.3V.
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Old Aug 16, 2012, 04:41 AM
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Yes, you helped me searching the right transistor . There is another thing about this transistor. I don't know if it is a faulty about Walkera transmitter that have a problem when working with different types of batteries. The fact is that with Ni-Mh, the transmitter doesn't advise with sounds when the power is low. It could be in relation with the value of the internal diode of the P-Mosfet transistor. Probably the transistor that I have provided has a lower internal diode value. I'll try by putting a diode to add an additional value of around 0.5V to see if the alert of low power runs.

I suppose that the microcontroller has an input with an A/D converter to know the level of battery but I don't know if the measure is before or after the P-Mosfet. I suppose it is after, so modifying the value of the internal diode could be sufficient.
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Old Aug 16, 2012, 07:53 AM
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Any update on when the Big Firmware Release will be?
I still haven't got my Devo 8 yet.
Sorry if I missed something. 😃

I am sure you guys are going to sell a lot of TX's for Walkera. Hopefully they know this and send you guys a 12's or something. <---------------------------WALKERA LOOK HERE
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Old Aug 16, 2012, 07:56 AM
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Just received a message from someone who has a headtracking device and Devo. Unfortunately it's not working out of the box He couldn't tell me why it's not working but I have a few suspicions. The way I see it, it might be possible with alterations to the firmware, if the DSC port can process the signal to begin with.
here's a link to the cable http://www.hobbyking.com/hobbyking/s..._1_meter_.html can anyone shed some light on how the DSC plug works? (i.e how many pins and what they do?)
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Old Aug 16, 2012, 11:27 AM
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Wonderful thread. I just bought a devo8 with GCP for the intend of hacking the TX.
From what I read, devo8 should work for the hacked firmware. Does the 8-> 8s
upgrade module worthwhile to buy? It is only $10.
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Old Aug 16, 2012, 03:49 PM
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The 8s module allows you to get telemetry like battery voltage and motor temperature, so i recommend you get it.
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Old Aug 16, 2012, 07:07 PM
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Quote:
Originally Posted by printk View Post
Wonderful thread. I just bought a devo8 with GCP for the intend of hacking the TX.
From what I read, devo8 should work for the hacked firmware. Does the 8-> 8s
upgrade module worthwhile to buy? It is only $10.
What is GCP?

Edit: Duhh Genius CP. forget I asked. lol
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Old Aug 16, 2012, 08:37 PM
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Any update on when the Big Firmware Release will be?
I still haven't got my Devo 8 yet.
Sorry if I missed something. 😃
No update yet, but progress is moving along steadily. We've made a lot of progress getting the actual Transmitter working properly.
FDR has been busy finding bugs when using the Tx.
Wiuselfuzz has been busy cleaning up my crappy code.
I've been busy fixing the issues that have been uncovered, and trying to get the rest of the necessary features implemented.

At this point, the following need to be done before releasing the 1st alpha for the Tx:
* Don't enable the radio until the sticks are 'safe'
* Improve reliability
* Range test

That 2nd one is really the killer, and I don't know how long it'll take.
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Old Aug 16, 2012, 11:50 PM
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I got my Devo10 today along with my MiniCP (it is 3-axis by the way). I immediately put the mini on the shelf, shoved some batteries into the Devo10, powered it on (just to make sure it worked), turned it off, put it in Program mode, and uploaded a test program to it. when I rebooted, it immediately spit out the 'hello' message on the UART (printf working on 1st boot), and on the 2nd programming I had the power switch working

I don't like that there is no LED to tell you when it is on, but once I know something about the LCD, I'll probably just use the backlight for the same capability. I guess I need to crack-open the case to dig around and see how stuff is connected, but I'm pretty happy that the 10 is similar enough to the 8 that basic initialization worked out of the box. I expect it to be trivial to get everything other than the LCD functional.

I definitely need to rethink the code layout though so I can share the Devo functions across the models.

I probably won't spend too much time on the 10 until we get the initial release for the 8 done though.
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Old Aug 17, 2012, 12:12 AM
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I built a temporary clone of the deviation code for the Devo10. It can be found here:
https://bitbucket.org/PhracturedBlue/deviation10

The dfu file generated gets through init, and sends basic SPI and CYRF6936 info to UART. It also has simple button-testing code. The filesystem and LCD code is disabled.
Only about half the buttons work, so the Devo10 has a different button matrix than the 8, but it still uses the same basic configuration. Now I'm really done with the Devo10...at least for a couple days.
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Old Aug 17, 2012, 01:17 AM
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Excellent work PB,FDR and Wuselfuzz.

Thanks, Phil
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Old Aug 17, 2012, 02:23 AM
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I finally managed to compile the firmware and put it on my new 8s. Excellent work, it's really beautiful.
I wanted to test some DSM stuff but don't managed to find any kind of binding function. Can you just give me a short hint?

Thanks,
Boris
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Old Aug 17, 2012, 02:48 AM
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I finally managed to compile the firmware and put it on my new 8s. Excellent work, it's really beautiful.
I wanted to test some DSM stuff but don't managed to find any kind of binding function. Can you just give me a short hint?

Thanks,
Boris
Turn on the tx, and within a few seconds connect the battery to the rx.
At least this is the auto binding sequence for Walkera stuff, but it might be implemented the same way.
Unfortunately I don't have any DSM2 compatible rx to try...
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Old Aug 17, 2012, 03:40 AM
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Originally Posted by PhracturedBlue View Post
I built a temporary clone of the deviation code for the Devo10. It can be found here:
https://bitbucket.org/PhracturedBlue/deviation10

The dfu file generated gets through init, and sends basic SPI and CYRF6936 info to UART. It also has simple button-testing code. The filesystem and LCD code is disabled.
Only about half the buttons work, so the Devo10 has a different button matrix than the 8, but it still uses the same basic configuration. Now I'm really done with the Devo10...at least for a couple days.
Seriously? You got my attention here... Cloning your repo when I get off work!!! (BTW, I don't have UART, so anything I can check to indicate anything works at all?
Thanks a lot PB!!!
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