Joystick and Bluetooth Module
Posted 25 February 2012 - 06:56 PM
1. What is the difference between the two joysticks that I've put a link for? My personal preference is the first one since the other is out of stock and since I'm buying all the stuff from www.hwkitchen.com
2. Imp: How do I connect the joystick to the breakout board? Is the breakout board used to connect I/O device to a Development board?
3. And do you have any guides to share for me on how to connect and program these devices on the Netduino. Best I found for bluetooth is this Link (which I'm hoping RN-41 and RN-42 are no different to connect and program). I found nothing yet regarding the joystick. Please share with me some guides that you know on these two subjects as I'm still new on this.
4. And anyone bought from HW Kitchen before?
Thank you in advance
Posted 25 February 2012 - 09:30 PM
The first joystick uses a pair of 10,000ohm (10Kohm) potentiometers, and a push switch.
The breakout board brings all of these to a 5 way connector. Its left up to you to decide how you connect the board to your microcontroller - wires, 0.1" header etc.
The schematic shows the switch is wired up so that the switch output is connected to ground when pressed. There is no pullup resistor on the switch or board, but the Netduino has an option for input ports that allows you to enable a weak pullup.
There is nothing on the back of the breakout board (apart from component legs protruding through the holes) so it could be mounted flat on something solid. Depending on how much punishment you think it will get, this could be important as you will be able to support it from the rear.
I can't see any information describing the guts of the second joystick.
Looking at the schematic on another site, it looks like it is also a pair of potentiometers and a switch.
The built in breakout board has a pull up resistor for the switch so when you press the switch it will take the switch output signal low.
I also found a 3D PDF of the board, and from this, you can see that to use the second joystick you need to connect to the connector on the back of the joystick. You won't be able to mount the board flat on something else. So the board is more likely to bend as it is pressed.
With the first joystick, you will need to insert the joystick into the board and solder the pins to the board on the rear.
You will also have to solder something to the five 0.1" spaced holes on the board. You might just solder five wires directly to the board and run them to the Netduino, or you might solder a 0.1" 5 pin header to the board, and make up a cable with a five way socket on the end that pushes onto it. The other ends of the wires can just be pushed into the header sockets on the Netduino.
With the second joystick, the module appears to be pre-assembled (no soldering).
I can't tell if they sell a ready made cable with the required socket already fitted - so you may have to make that yourself. If you can buy it ready made, then I would expect you can run it to the Netduino and push the wires into the Netduino header sockets.
For both joysticks, connect
- the ground of the Netduino to the joystick ground
- the 3.3V of the Netduino to the joystick Vcc
- two of the analogue inputs on the Netduino to the wiper signals of the potentiometers (labelled HORZ and VERT on the first joystick, or pins 4 and 5 on the second joystick)
- one digital pin on the Netduino to the switch (labelled SEL on the first joystick, or pin 3 on the second joystick)
- ignore the 5V connection (pin 2), it does not appear to be required.
I can't advise you about the Bluetooth module - search the forums there are quite a few hits for the word Bluetooth and some talk about the RN-41 / RN-42.
Software for using either potentiometer is really simple, you can just setup three inputs (two analogue and one digital) and read them periodically to start with. (You will get a number on the analogue inputs that will be proportional to the X and Y positions of the joystick.)
The digital input can be setup to have an event that you could use to trigger some action as soon as the button is pressed.
I have never bought from Hardware Kitchen.
I'm in the UK, and I have used Hobbytronics many times now.
They have the same joystick, but instead of a breakout board, they sell an Arduino shield kit from sparkfun that includes the joystick and a PCB to connect it to. The shield kit also includes four push buttons.
Note that the shield is designed for a 5V Arduino - so when you assemble it you need to route the Netduino's 3.3V to the shield's 5V pin. (Otherwise the analogue voltages will be too great at one end of the joystick travel.)
If you do chose to use this shield - check that the signals used for the Bluetooth module are not used by the shield. (For example, the shield uses A0 and A1 - these are also the Netduino I2C pins. Does the Bluetooth device need these.....) Since the shield is in kit form this would not be a show stopper, but it will complicate things a little.
- xikky likes this
Posted 26 February 2012 - 12:18 PM
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users