RC-USB Joystick Files - Page 12 - RC Groups
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Feb 05, 2009, 11:54 AM
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Any help?
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Feb 10, 2009, 05:53 AM
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Someone has already done this work?
Feb 10, 2009, 11:42 AM
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If you have modified Alessio's code then try droping him a PM or e-mail via his website
Feb 10, 2009, 05:28 PM
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I only modified the file rcjoy.asm according to the instructions on this forum.

I am sending attachment.

As I said, what's intrigued me is the fact that JP4 is open or closed the interface is configured only as JR. I remove the USB interface and do it again and still set on JR. It is as if RC0 was always getting a signal. But I measured with multimeter and it is not closed. This leads me to believe that there is something wrong with the file.

So I wonder if someone managed to make it work?

If I comment on the sentence JR and compile the file it works normally as Futaba.
Feb 11, 2009, 01:24 PM
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As its been a few years since Steve and I played about with modifying Alesio's original code i don't have all the testing rigs we used. Plus at the time I used a JR tx and Steve had a Futaba, so I can't confirm the points you are making. However I would of thought that if the code was wrong a lot of other people who have built the interface originally would have reported the issue.

If I get chance at the weekend I'll see if I can have a look at the files and see if there anything obvious.
Feb 11, 2009, 05:16 PM
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Okay, thank you for your attention.

I agree with you, so I at least find a person able to work. I already checked the electronic diagram, gives the file with the code. Frankly I can not understand why it does not work. Frankly I'm quitting.

Anyway, thank your attention!
Feb 15, 2009, 02:26 PM
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Ok, bit rusty as I've not looked at this code for almost three years + Mark J was the chap that done most of the coding.

I've not had chance to breadboard this at all this weekend, but reading through the thread and trying to discover what may be the cause I note that we originally use one of the pins of RB port rather than RC port. My guess is that we missed something in the configuration part of the code and have not made RC0 digital.

movwf	ADCON1, ACCESS				; set up all ports pins as digital I/Os

			clrf	TRISA, ACCESS				; PORTA pins all output

			movlw	B'01000000'
			movwf	PORTB						; PORTB: RB6 high, all others low
			movlw	B'10000001'
			movwf	TRISB						; PORTB: RB0/INT and RB7 as input, all others as output
			bsf		INTCON2, RBPU, ACCESS		; weak pull-up disabled
Maybe if you could set RC0 as an input in much the same way as PORT B's RB7 than this may indeed work.

If that don't work then simply program the chip with the version you need. This was probably why we produced two versions of the code, one with for JR and the other for Futaba.
Feb 17, 2009, 01:37 PM
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I believe it is easier to change the circuit to test RB7 origianal. Instead of testing RC0 I put JP4 to test in RB7 and leave the original file testing in PORTB.

So I do the test I put the result here.

I think the trouble! I will do a test!
Feb 19, 2009, 11:01 AM
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I made a new test. As the diagram below I called JP4 on pin RB7. Then rewrite the PIC with the original version.

When I realized that the test now the pic is getting to test the port RB7. When JP4 is open RCJoy is set as the JR. But when closing the circuit JP4 is crazy. He is set to FUTABA and JR together. It is understood that only Futaba.

	btfsc		PORTB, 7, ACCESS		; RB7 low
	goto		ReadChAssignFutaba		; no, Futaba radio
ReadChAssignJR							; yes, JR radio
	; prepare table pointer
	movlw		low JRAssignment
	movlw		high JRAssignment
	movlw		upper JRAssignment
	movwf		TBLPTRU, ACCESS			;TBLPTR points to first byte of table
	goto		ReadAssignTable
	; prepare table pointer
	movlw		low FutabaAssignment
	movlw		high FutabaAssignment
	movlw		upper FutabaAssignment
	movwf		TBLPTRU, ACCESS			;TBLPTR points to first byte of table
	goto		ReadAssignTable
If I back it is only open JP4 JR, closing again when he JP4 is Futaba and JR together.

It is as if he were to close JP4 an "AND", not an "OR"
Last edited by nyxtech; Feb 19, 2009 at 11:19 AM.
Mar 02, 2009, 07:08 AM
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Finally solved the problem. Find out what happened.
The first test project using RC0 for Futaba / JR was not correct. According to the pic datashet this pin is not intended to be used this way. To perform this type of test you must use the pin RB7.

That is what I did, I made a jumper between JP4 and RB7 and canceled on track to RC0 that would make it irrelevant.

When did the first test, I realized that was really testing, but when I activated the key to select the futaba interface was confusing and just running the two together.

RB7 testing with the multimeter realized that when selecting JR pin received around 6V, and when I selected the pic had a Futaba internal voltage of 0.03 v. I noticed that the pic was not grounded and therefore generated confusion.

Soldered a 1k resistor on pin RB7 to pin 1 of the USB input. And the problem is resolved.

Selecting JR he received 6v selecting Futaba he received 0V.

Therefore the issue is fully resolved and now works perfectly!
Mar 15, 2009, 02:42 PM
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I have a 16mhz crystal laying around and didn't want to order w/shipping a 4 mhz. Is it simple to change to 16 or should I just bite the bullet and order a 4mhz crystal?
Mar 15, 2009, 04:46 PM
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I'm sure you could change the timings to suit, but to be honest I'm not sure exactly how and where you would need to edit the code
Mar 15, 2009, 07:00 PM
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Ok, Tyvm. I'll just order a crystal.
Mar 23, 2009, 11:04 AM
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3axis joystick tx! Use your joystick to fly!

the logitech extreme 3d pro joystick is a 5v sysytem and can be wired into the spectrum dx6i tx and probably any others that are 5v systems as well... i did test one pot...i unplugged one connector in the tx and plugged one of the pots from the logitech into its slot and when i rotated the pot it moved the corresponding servo on my heli! Only question is are the pots compatable? If so the dx6i has a builtin calibration tool for the pots so you would be able to calibrate them! to custom build this i need to find some 6or 7 pin connectors ....some crimping tools and the little connectors. i didnt want to splice into the tx wires.... i could but dont want to void warranty.....i have since mastered the two stick system and have not done anything else but i think it can be done. I can see the whole stick removed from the joystick and transplanted into the tx...a true 3axis rc joystick tx!
Last edited by leadtongue; Mar 23, 2009 at 11:12 AM.
Aug 18, 2009, 09:41 PM
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New here. Just wanted to thank the makers of this - saves me the trouble of doing it myself.

I slapped it together with a 2N3904 and it works with my Futaba T6XA. I use 20MHz crystals for all of my uC projects so I made some changes for that.

Thanks again,

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