BOE-USB manual v1.4

Power Supply Clip and Barrel Jack (top left): The 9 V battery clip and the barrel jack are positioned so

that they cannot be accidentally used at the same time. For the jack we recommend our 9 VDC V 300 mA

supply, # 750-00008.

Power Switch (bottom center): The leftmost position (0) is OFF – all power is disconnected. Always

place the switch in position-0 when changing components on the breadboard, and when disconnecting or

reconnecting to the PC. The middle position (1) provides Vin to the regulator, the BASIC Stamp IC

socket, and to the connectors marked Vin. In this position, Vdd will also be available on the breadboard

and AppMod (see below) connectors. The rightmost position (2) provides power to the servo connectors

X4 and X5 (see servo power selection below). The three-position position power switch is convenient

when using the BOE-USB on small robots, like the Parallax Boe-Bot

. Use position 1 to edit and test

code while power is removed from the servos.

Servo Ports (X4 and X5), and Power Selection (top right): Select the power provided to servo sockets

X4 and X5 by the jumper located between them; the default position is Vdd (+5 V regulated). When using

a six-volt battery pack (as on a Boe-Bot robot), you may wish to move this jumper to the Vin position to

provide extra power to the servos. When using Vin in the servo ports, always check to make sure the

voltage supplied does not exceed the specifications of the particular brand of servos you are using. X4

and X5 connect to the BASIC Stamp I/O pins labeled above the sockets; do not build incompatible circuits

connected to the same I/O pins on the breadboard when using X4 or X5. Always check the pinout and

voltage requirements of 3-pin devices before connecting them to X4 or X5.

Reset Button: The reset button can be used to restart your BASIC Stamp IC without having to cycle the

power. This saves wear-and-tear on the power switch for simple program restarts.

Breadboard Access for BASIC Stamp I/O (X2), Vdd, Vin, and Vss (X3): The BASIC Stamp IC’s 16 I/O

pins are brought to the X2 female socket left of the breadboard. I/O pins are accessed by plugging wires

into the header, then into the breadboard sockets. The X3 socket provides four connection points for a

+5V (Vdd) connection, unregulated input voltage (Vin), and ground (Vss).

AppMod Header (X1): provides connection and signal routing for 20-pin AppMods, the eb500

EmbeddedBlue Transceiver (#30068) and the LCD Terminal (#29121). All I/O pins, Vdd, Vin, and Vss

are routed through the AppMod connector. The BASIC Stamp I/O pins used by a device in the AppMod

Header should not also be used with conflicting circuits on the breadboard area. Please refer to the

individual AppMod product documentation for device pin maps.