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Hardware

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(1) Power Switch – used to turn the board on and off.  The board must be externally powered through either the 12V DC input jack or through the battery wire.  Plugging the USB cable into the board does not provide any power to the board.

(2) 12V DC Input – the board is fully functional with a DC input 12 to 15V.  The Wiring board, LCD and all digital logic works at voltages greater than 7V, but the motor outputs will not operate properly at voltages less than 12V.  The DC input jack is center-positive.

(3) Battery Output – this screw-down header connector gives direct connection to the battery connected to the TINAH board.   This connection can be used to connect the battery to any external circuitry (external motor drivers, sensors/switches which require power, etc).

(4) and (5) Stop and Start Buttons –  The buttons are named start and stop, but can be used interchangably depending on the code that you write, using the stopbutton() and startbutton() commands.    Commands can be found in the Software writeup.

(6) Motor outputs and indicators –  4 motors can be controlled using the setup (Motor 0, 1, 2, and 3).  The LEDs indicate the direction and intensity of the motor (brighter = higher PWM = faster motor).  Commands for using the motors can be found in the Software writeup.

Motors can be connected directly to the board through either the screwdown terminals, or the header pins immediately to the left of the screw terminals (they are electrically connected).  The figure below shows the groupings for the screw terminals and the header sockets for the motors.

Figure:  Motor Output Headers



The header pins are in groups of 3 pins, with the middle pin not connected to anything; this means that a motor on a 3-pin header will not be powered in case the motor is accidentally shifted over by a single pin on the header.

The TINAH board limits the output of the motors connected to 9V at a maximum of ~700 mA per motor (the board uses an H-bridge chip, the SN754410NE, with power through a 7809 regulator) .  Any motor with larger voltage or current requirements should be driven with an external H-bridge controller using the signals generated using these inputs/outputs or the motor control signal outputs described below.

(7) Motor control signal outputs  –  these digital logic-level signal outputs are meant to connect with an external H-bridge or other motor control circuit for arbitrary current or voltage requirements.  See the information for the H-bridge chip used on the TINAH, the SN754410NE. This is similar to many types of single-chip H-bridge chips as well, such as the L293D.   These are signal outputs, and do not source or sink sufficient current to directly to power a DC motor. 






(8) Servo Motor Outputs – The servo motor outputs can be connected as shown.  The board can take any standard RC servo motors, as explained here with a default 5V power connection as shown.   Take care to insert RC servo motors into the plug-in headers so that the Signal Line is connected to the motor correctly (typically the white or yellow line).  Commands for using the servo motors are found on the Software page









(9) Reset Button – this button is to be pressed when a program is uploaded to the board through the Wiring environment.  Press the button within ~5 seconds of pressing the “Upload to I/O Board” button.

(10) Digital Inputs – 16 digital input lines grouped into two ports (Port0 and Port1).

The pinout convention matches the setup used in the Handy Board, with a sensor signal pin, a gap, followed by a row of 5V and ground.







(11) Analog Inputs – 8 analog input lines, with 0-5V input range.   Note that Analog Inputs 6 and 7 are tied to the two knobs, but can be redirected to the Analog Input header by changing the jumper settings next to the knobs.






The pinout convention matches the setup used in the Handy Board, with a sensor signal pin, a gap, followed by a row of 5V and ground. 







(12) PWM Outputs – provide access to the 6 PWM output lines from the  Wiring board.  Four of these lines (PWM 0, 1, 4, and 5) are assigned to the motor outputs, but can be used as general PWM or digital outputs if motors are not connected to the outputs.  Commands for using the PWM outputs are found on the Software page




• PWM pins 5, 4, 3, 2, 1 and 0 map directly to digital pins 29, 30, 31, 35, 36, and 37.  This is part of the Wiring board default setup.  See here for an explanation from the Wiring documentation.
• The PWM pins are all normally connected to other functions on the TINAH board.  A pinout diagram can be found here.
  • PWM 5, 4, 1, and 0 are connected to the enable signal of the motor drivers, and are normally used to provide the PWM output for motors 0, 1, 2, and 3.
  • PWM 2 is normally connected to RCServo1, and becomes active when the RC Servo is initialized with “RCServo1.attach(RCServo1Output)”
  • PWM 3 is normally connected to RCServo2, and becomes active when the RC Servo is initialized with “RCServo2.attach(RCServo2Output)”  PWM 3 is also connected to the on-board Buzzer, which at the moment has been disabled.
• An excerpt from the full pinout table for the TINAH board:

   

  Wiring digital Pin#	Wiring PWM Pin #	TINAH Function
  29	5	Motor_En 0
  30	4	Motor_En 1
  31	3	ServoOut1/Buzzer
  35	2	ServoOut 0
  36	1	Motor_En 2
  37	0	Motor_En 3

   




(13) Rx/Tx Indicators – LEDs indicate when there is communication along the USB/Serial port interface to the main computer.   This occurs if either the board is being reprogrammed, or if information is being transferred to or from the main computer using the Serial library commands.

(14) LCD Screen – 16 column x 2 row LCD display.  Use the LCD commands as described in the Software writeup to write information to the screen.

Note that the LCD does not automatically reset when the Reset Button is pressed.  This means that the program may be halted and a new program received and downloading while the LCD displays the most recent update, sometimes for several seconds while the program is downloading.

(15) Power Indicator – On when the TINAH board receives sufficient power to operate.

(16) and (17)  Knobs Access the value of the two knobs by calling the knob functions knob(6) or knob(7).  Can change the jumpers in order to connect Analog Inputs 6 and 7 to the analog input header pins instead of from the knobs: