28301 Parallax Inc, 28301 Datasheet - Page 4

• Manufacturer Part Number: 28301
• Description: DAUGHTERBOARD 3PIN I/O MOBO
• Manufacturer: Parallax Inc

Specifications of 28301

• Accessory Type: Daughter Board, Power and I/O Interface
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: MoBoStamp, MoBoProp
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Interfacing External Devices
This section gives examples of how to interface various external devices to the daughterboard. However,
the range of devices that can be plugged in is not limited to those in the examples and includes the
following Parallax products (with part numbers):
Servos
Servos can be connected to any of the six headers. However, for servos to work on A0 and A1, there
needs to be special firmware loaded into the AVR to pulse them. Such firmware could also pulse servos
connected to A2 and A3. Servos connected to A2, A3, P8, and P9 can be pulsed directly from the BASIC
Stamp.
A typical servo installation will look like the following:
Serial Devices
Serial devices, such as LCD displays, interface readily to the PWR-I/O-DB. They can be connected using
the Parallax “LCD Extension Cables” (#805-00011 and #805-00012). A typical LCD installation is shown
below:
© Parallax, Inc. • PWR-I/O-DB (2006.09.13)
Important: The power provided at the external device headers is always +5V, regardless of your
Vdd selection on the motherboard. This may have unintended consequences if your motherboard is
running with a Vdd of 3.3V. For most devices where the signal line is an output to the device (e.g.
servos and serial LCDs), this should not be an issue. But for 5V-powered devices that provide an
input to the daughterboard (and, hence to the motherboard), the incoming signal level could exceed
the safe level for 3.3V operation. In such a case, use a Vdd of 5V instead, or apply external current
limiting to the incoming signal.
Important: When using the PWR-I/O-DB with servos, be sure to use as low a voltage on Vin as
possible to keep the 5V regulator from overheating – especially during stall conditions.
To Wall
Transformer
Ping))) Ultrasonic Rangefinder (28015)
2x16 Serial LCD (27976, 27977)
4x20 Serial LCD (27979)
Standard Servo (900-00005)
Standard Continuous Rotation Servo (900-00008)
Mini Servo (900-00010)
LM34 Temperature Probe (800-00027)
DS2760 Thermocouple Kit (28022)
QTI Line Sensor (555-27401)
Passive Infrared (Motion) Sensor (555-28027)
J1 6-9VDC
A1 A0 A3 A2 P8 P9
DB 5V MB
Vin J1
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