HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Sep 05, 2007, 06:54 PM
VE7FM
TheSteve's Avatar
Canada, BC, Langley
Joined Nov 2004
1,724 Posts
Possibly, usually micro controllers have a dedicated hardware UART built in thats nice to use.
TheSteve is offline Find More Posts by TheSteve
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 05, 2007, 07:27 PM
Formerly P4 Hover
San Jose, California, United States
Joined May 2003
373 Posts
Just wondering here....

Could this be done on a PIC12F275 with bit bainging serial out? Only reason I ask is I am sightly more sided to the PIC line and we only need 2 IO pins.

-Jon
Zeta Phoenix is offline Find More Posts by Zeta Phoenix
Reply With Quote
Old Sep 06, 2007, 09:28 AM
Inciting Riots
village_idiot's Avatar
Joined Dec 2006
9,687 Posts
Other companies seem to be able to use PIC MCUs so I don't see why not. Plantraco uses a PIC16 series, not sure what XPS is using for their stuff, but I know it is PIC based.
village_idiot is offline Find More Posts by village_idiot
Reply With Quote
Old Sep 06, 2007, 09:43 AM
User
Colorado
Joined Oct 2004
1,424 Posts
XPS is also using PIC16 series (in particular the PIC16F91x in an SO package, if I'm not mistaken).
rmteo is offline Find More Posts by rmteo
Reply With Quote
Old Sep 06, 2007, 12:13 PM
VE7FM
TheSteve's Avatar
Canada, BC, Langley
Joined Nov 2004
1,724 Posts
There is no reason a PIC can't do it. I'd select one with a ICP (input capture pin) and a UART to make your life simple though. To get the 1us timing required you only need a 4Mhz clock if using a 4:1 prescaler.
Capture the data and write each channel value to an array. Check it for min/max safe values. Re-order the channels if required, limit to 6 channels, add the Spektrum DSM2 channel marking bits and send out the UART after sending 2 bytes of 00.
That all thats required.
TheSteve is offline Find More Posts by TheSteve
Reply With Quote
Old Sep 07, 2007, 03:08 AM
VE7FM
TheSteve's Avatar
Canada, BC, Langley
Joined Nov 2004
1,724 Posts
Having done many flights I have full confidence in the system.
I did some range testing tonight, it certainly works further then you can fly a small heli, more range then I figured 2mw would give.
Is there anyone seriously interested in building a version of this?
We do have some small PCBs that fit a smt tiny2313, regulator, crystal and a few caps, it would simplify building the ppm to serial converter(if you like soldering smt) It also happens to fit an xbee module should you ever want to go that route.
Its really quite simple in terms of hardware, PPM data into the Atmel, serial data out.
If there really are some people that want to build this I will consider posting the .hex and the C code.
TheSteve is offline Find More Posts by TheSteve
Reply With Quote
Old Sep 07, 2007, 09:29 AM
Inciting Riots
village_idiot's Avatar
Joined Dec 2006
9,687 Posts
I'd be interested in the schematic and C code for the PPM to anything code so I can get going on bulding my own stuff. I'll have to reread your posts about hacking out the serial data for something I want to try, probably a 900Mhz system. Since I don't have a dev kit (yet) for PIC or Atmel I'm not really favoring one over the other.

I'd like to start by making a Plantraco compatible system, then maybe getting it to frequency hopping, and then boost the power up to the 1 watt ERP that's allowed in the USA for FHSS on 900Mhz. The gear seems to work well enough now, but jumping the power up would give it full range (and then some). I'll have to look into Atmel dev kits this weekend and see what I can find.
village_idiot is offline Find More Posts by village_idiot
Reply With Quote
Old Sep 07, 2007, 11:43 AM
Formerly P4 Hover
San Jose, California, United States
Joined May 2003
373 Posts
Quote:
Originally Posted by TheSteve
Having done many flights I have full confidence in the system.
I did some range testing tonight, it certainly works further then you can fly a small heli, more range then I figured 2mw would give.
Is there anyone seriously interested in building a version of this?
We do have some small PCBs that fit a smt tiny2313, regulator, crystal and a few caps, it would simplify building the ppm to serial converter(if you like soldering smt) It also happens to fit an xbee module should you ever want to go that route.
Its really quite simple in terms of hardware, PPM data into the Atmel, serial data out.
If there really are some people that want to build this I will consider posting the .hex and the C code.
Well, count me in! I was asking on using the PIC chip, as I was going to build my own, but if you would be willing to release, I'm all over it!

-Jon

P.S.: I am not afraid of SMT. I have done some 0402 rework on a damaged GY240!
Zeta Phoenix is offline Find More Posts by Zeta Phoenix
Reply With Quote
Old Sep 07, 2007, 07:04 PM
^-- breaks stuff
nihil's Avatar
Joined Apr 2004
963 Posts
Count me in, I had my cx2 tx taken apart and was eyeballing that module myself, but never got around to messing with it:
http://nihil.rchomepage.com/helicopt...bcx2tx1385.jpg

I've also been looking at the xbee pro, being disappointed with the bandwidth and range of bluetooth modules. On top of that, I've got some 2313's sitting here doing absolutely nothing important.

Where do we get the schematic and code?
nihil is offline Find More Posts by nihil
RCG Plus Member
Reply With Quote
Old Sep 08, 2007, 11:37 AM
Registered User
Snohomish, WA
Joined Jun 2007
120 Posts
I'm definately in, although I'm admittedly more interested in the possibility of a full range Xbee pro system. Now as for modifying everything to link directly to the Microstar, I'm hopeless. I know my way around circuits and schematics to build and troubleshoot, but I'm a mechanical guy. No code writing for me.
blanchjd is offline Find More Posts by blanchjd
Reply With Quote
Old Sep 08, 2007, 03:16 PM
Inciting Riots
village_idiot's Avatar
Joined Dec 2006
9,687 Posts
Yes, it's a challenge for me too as I have very little coding experience. But I'll never learn if I never start, so starting with examples that I can dissassemble to pair up with what I can find in a book should eventually lead to success (hopefully).
village_idiot is offline Find More Posts by village_idiot
Reply With Quote
Old Sep 09, 2007, 07:15 AM
Registered User
Richard Ingram's Avatar
Birmingham, AL
Joined Aug 2002
276 Posts
I have beenn following this thread and would also be interested.

Thanks
Richard Ingram is offline Find More Posts by Richard Ingram
Reply With Quote
Old Sep 09, 2007, 07:35 AM
I don't want to "Switch Now"
pmackenzie's Avatar
Toronto (Don Mills), Canada
Joined Dec 2002
16,552 Posts
What about binding?
Is that all handled by the DSM2 chip that came from the CX2 transmitter?

Thanks,

Pat MacKenzie
pmackenzie is offline Find More Posts by pmackenzie
Reply With Quote
Old Sep 09, 2007, 03:11 PM
VE7FM
TheSteve's Avatar
Canada, BC, Langley
Joined Nov 2004
1,724 Posts
Quote:
Originally Posted by pmackenzie
What about binding?
Is that all handled by the DSM2 chip that came from the CX2 transmitter?

Thanks,

Pat MacKenzie
Yes, thats the beauty of the DSM2 module from the LP5DSM - it handles everything. When you first power on the LP5DSM it goes into binding more for a few seconds(LED flashes) then goes to normal mode. They only do this on the LP5DSM because its very low power. The advantage to us is that we don't have to add any bind buttons or worry about it. The output to the LED thats normally flashed on the front of the LP5DSM transmitter is now connected to the RF good indicator on my Futaba 9CAP, so I still see the flashes and know when its ready to go.
TheSteve is offline Find More Posts by TheSteve
Reply With Quote
Old Sep 09, 2007, 04:37 PM
I don't want to "Switch Now"
pmackenzie's Avatar
Toronto (Don Mills), Canada
Joined Dec 2002
16,552 Posts
Then how does the rcvr know "your" TX from anyone elses?
Or does this only work because you bought them as a pair with the original CX2?

Pat MacKenzie
pmackenzie is offline Find More Posts by pmackenzie
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Anybody ever ask you "Why don't you build your own planes?" juantrinidad Electric Plane Talk 21 Feb 26, 2003 09:34 PM
FS: Build your Own Lithium Packs Cheap jcherry Aircraft - Electric - Airplanes (FS/W) 0 Dec 15, 2002 08:01 AM
What's A Good Program To Build Your Own Website For A Begginer? Joe Elston Life, The Universe, and Politics 12 Oct 16, 2002 04:29 AM
Sites on how to build your own batt ZAPPER Kevin Graehl Batteries and Chargers 28 Aug 29, 2002 01:53 AM
Build Your Own Defense Budget CoastalFlyer Life, The Universe, and Politics 6 Jun 02, 2002 03:12 AM