Pioneer 2 - Manual (Page 18)

Specifications and Controls
12
A Main Power switch at the back of the robot controls power for the entire system. Processor control
switches and indicators fit through the Deck Console.
Power/Motor Board
Inside the robot, mounted to the battery box, is the Pioneer 2 Motor-Power board. It supplies both the
twelve and five VDC power requirements of Pioneer 2's standard systems. Additionally, it has user-
accessible five and 12 VDC connectors, which supply 1–2.5 amperes of power for accessories, depending
on configuration. The Motor-Power board also contains the motor-driver electronics, as controlled by the
microcontroller.
The standard Motor-Power board has a 12-pin user-power connector that supports four sets of five- and 12
VDC power ports (total one ampere) for custom accessories. An optional computer-power section to the
board supplies up to seven amperes at five VDC power for an onboard PC. The power board includes
special low-power and power-down circuit that lets you gently shut down the computer without direct
connection through a keyboard or monitor. (See Appendix B in this manual and the Computer Tech Notes
pamphlet that accompany the Pioneer 2 for details.)
Microcontroller
Pioneer 2's microcontroller uses a 20 MHz Siemens 88C166 microprocessor with integrated 32K flash-
ROM. The microcontroller also has 32K of dynamic RAM, two RS232-compatible serial ports, several
digital and analog-to-digital, and PSU I/O user-accessible ports, and an eight-bit expansion bus. See
Appendix A for port details.)
All the I/O ports, except those used for the motors, encoders, and sonar, are available to the user for Pioneer
2 accessory hardware, which you may control through the P2OS. Port connector pinouts and electronic
details appear in the Appendices.
Sonar Boards
Associated with each sonar array

forward and rear

is a sonar multiplexer / firing board. Wire leads
to the individual sonar plug into a 16-pin connector on the board. A 10-conductor signal cable connects
the sonar board with the microcontroller.
Controls, Ports, and Indicators
Main Power, Fuse, and Indicator
A single slide-switch on the rear left panel of the Pioneer 2 DX, AT and CE models controls power to the
entire robot and all its integrated accessories. Up is ON; down is OFF. A red LED on the Console indicates
Main Power.
Inside, on the top right side of the battery box (accessible through the hinged back door of the Pioneer 2
DX and AT) is the Main Power Fuse. It is an automotive-type (spade terminals) 15A (DX, CE) or 30A
(AT) fuse designed for tool-less replacement. To the left of the fuse, on the same board, is the main power
relay, which isolates the high-ampere draw of the robot system from the Main Power Switch.
Recharge/Power Port
Below the Main Power Switch is the battery Recharger port. It provides 12 VDC power to the robot's
electronics, motors, and accessories, even without batteries. Use the recommended accessory power
charger or equivalent.
You should maintain Pioneer 2’s batteries in a charged state above 11 VDC, as indicated on the robot’s
LCD. We recommend recharging the battery when it falls below 11 VDC, even though the robot may
continue to operate below 10 VDC. The microcontroller will sound a warning when the battery voltage
falls below that set level (see Chapter 7, Updating and Reconfiguring P2OS), and the optional computer