Web Site: www.parallax.com Office: (916) 624-8333 Forums: forums.parallax.com Fax: (916) 624-8003 Sales: sales@parallax.com Sales: (888) 512-1024 Technical: support@parallax.com Tech Support: (888) 997-8267 2-Axis Joystick (#27800) The 2-Axis Joystick can be used to add analog input to your next project. The 2-Axis Joystick contains two independent potentiometers (one per axis) that can be used as dual adjustable voltage dividers, providing 2-Axis analog input in a control stick form. The modular form-factor allows you to plug the 2-Axis Joystick directly into a breadboard for easy prototyping. The 2-Axis Joystick includes spring auto- return to center and a comfortable cup-type knob which gives the feel of a thumb-stick. Features (cid:1) Easy breadboard connection (cid:1) Two independent potentiometers with common ground (cid:1) Spring auto-return to center position (cid:1) Comfortable cup-type knob (cid:1) Compatible with most microcontrollers Key Specifications (cid:1) Power capability: 0.01W; 10 VDC maximum working voltage (cid:1) Interface: Dual 10 kΩ potentiometers with common ground (cid:1) Operating temperature: 32 to 158 °F (0 to 70 °C) (cid:1) Dimensions: 1.64" H x 1.40" L x 1.10" W (41.67 mm H x 35.56 mm L x 27.94 mm W) Application Ideas (cid:1) Camera Pan/Tilt Control (cid:1) Game Input/Control (cid:1) Robot Control (cid:1) Analog Input of Parameters Copyright © Parallax Inc. 2-Axis Joystick (#27800) v1.2 1/16/2012 Page 1 of 3

Quick Start Circuit This circuit works with the code below for the BASIC Stamp 2 to provide an RCTIME value for each axis that relates to the position of the joystick. In this manner the two potentiometers are providing a variable resistance for use with the RCTIME command. Caution: When using this circuit, do not use a resistor value less than 220 Ω and do not apply more than 5 VDC through this resistor to the L/R or U/D pins. For more information on how to measure resistance using the BASIC Stamp RCTIME command, please read Chapter#5 of What’s a Microcontroller? book, a free download at www.parallax.com/go/WAM. The PDF is also included in the BASIC Stamp Editor software’s Help file, which is a free download from www.parallax.com/basicstampsoftware. BASIC Stamp® 2 Program ' {$STAMP BS2} ' {$PBASIC 2.5} LR VAR Word UD VAR Word DO HIGH 4 PAUSE 2 RCTIME 4, 1, UD HIGH 11 PAUSE 2 RCTIME 11, 1, LR DEBUG HOME, "UD = ", DEC UD, CLREOL, CR, "LR = ", DEC LR, CLREOL PAUSE 50 LOOP Copyright © Parallax Inc. 2-Axis Joystick (#27800) v1.2 1/16/2012 Page 2 of 3

Advanced Circuit This circuit creates two voltage dividers referenced to VDD (in this case 5 V), using a 2-channel ADC (in this case the MCP3202) to read the voltages at the L/R and U/D pins using the code below. Caution: Do not apply voltage to the L/R+ or U/D+ pins that exceeds the I/O pin voltage rating of the device you connect to L/R or U/D, up to 10 VDC maximum. Ground<Analog voltage output at L/R and U/D<VDD. BASIC Stamp® 2 Program ' {$STAMP BS2} ' {$PBASIC 2.5} CS PIN 0 ' Chip Select (MCP3202.1) Clock PIN 1 ' Clock (MCP3202.7) DataIn PIN 2 ' --> Data Out (MCP3202.6) DataOut PIN 3 ' --> Data In (MCP3202.5) Cnts2Mv CON $0139 ' x 1.22 (To Millivolts) result0 VAR Word ' Conversion Result CH0 result1 VAR Word ' Conversion Result CH1 mVolts0 VAR Word ' Result0 --> mVolts mVolts1 VAR Word ' Result1 --> mVolts DEBUG CLS, "ADC CH 0:", CR, "Volts :", CR, "ADC CH 1:", CR, "Volts :" DO LOW CS ' Enable ADC SHIFTOUT DataOut, Clock, MSBFIRST, [%1101\4] ' Select CH0, Single-Ended SHIFTIN DataIn, Clock, MSBPOST, [result0\12] ' Read ADC HIGH CS ' Disable ADC mVolts0 = result0 */ Cnts2Mv ' Convert To Millivolts LOW CS ' Enable ADC SHIFTOUT DataOut, Clock, MSBFIRST, [%1111\4] ' Select CH1, Single-Ended SHIFTIN DataIn, Clock, MSBPOST, [result1\12] ' Read ADC HIGH CS ' Disable ADC mVolts1 = result1 */ Cnts2Mv ' Convert To Millivolts DEBUG HOME, CRSRXY, 9, 0, DEC result0, CLREOL, CRSRXY, 9, 1, DEC mVolts0 DIG 3, ".", DEC3 mVolts0, CRSRXY, 9, 2, DEC result1, CLREOL, CRSRXY, 9, 3, DEC mVolts1 DIG 3, ".", DEC3 mVolts1 PAUSE 100 LOOP Copyright © Parallax Inc. 2-Axis Joystick (#27800) v1.2 1/16/2012 Page 3 of 3