Pioneer 2 / PeopleBot

Pioneer 2 Operating System

sfSMessage("Port# % reads %i",sfRobot.timer, sfRobot.analog);

Port# 5 reads 33

sfRobotComInt(35,2);

sfSMessage("Port# % reads %i",sfRobot.timer, sfRobot.analog);

Port# 2 reads 224

DIGOUT and PSUPOS

The eight digital output ports on the P2OS controller’s User I/O connector are both

reported in the standard SIP (digout) and controllable with the P2OS commands DIGOUT

and PTUPOS. Electrically, the ports are digital high (1) at ~5 VDC (Vcc) and low (0) at ~0

VDC (GND).

For example, to read the state of the digital output ports with Saphira:

sfSMessage("Digout is %i",sfRobot.digout);

Digout is 240

Use the P2OS DIGOUT command to select and change the state of one or more of the

output ports at a time. DIGOUT takes a 2 byte (unsigned integer) argument. The first

byte is a mask whose bit pattern selects (1) or ignores (0) the state of the corresponding

bit in the second byte to set (1) or u nset (0) the digital output port.

For example, you might use Saphira to set digital output ports 1 and 3, reset port 4, and

leave all the rest alone (retain original state):

sfRobotComInt2Bytes(30, 0x19, 0x09);

The digital output ports OD0-4 may also be used for pulse-width-modulated (PWM)

control of accessories, such as DC motor speed or RC-servo motor position control. Use

the PTUPOS command to select a port (msbyte) and specify its pulse-width (lsbyte) in 10

µsecond units.

For example, to have a repeating one millisecond pulse appear on PWM port #1 (pin 1

on the User I/O connector):

sfRobotCom2Bytes(41,1,100);

You've got to disable a running PWM port to use it as a digital output port:

sfRobotCom2Bytes(41,1,0);

In P2OS versions 1.J and later, the duty cycle is 20ms, with a 0-2.55ms pulse corresponding

to common RC-servo applications.

IOpac and IOREQUEST

P2OS 1.E introduced a new server information packet in which your P2OS-based robot

controller reports all of its I/O-connected sensor input and output values in a single cycle.

Your client software must explicitly request IO packets; they normally are disabled. Use

the P2OS IOREQUEST command #40 with an argument value of 0, 1, or 2. The

argument 1 requests a single packet to be sent within the next cycle. The request

argument value 2 tells P2OS to send IO packets continuously, at approximately one per

cycle, depending on serial port speed and other pending SIPs. Use the IOREQUEST

argument value 0 to stop continuous packets.

The common IOpac contains three digital input bytes, User I/O digin and two bumper

state bytes, front followed by rear; one digital output byte (digout); and five analog-to-

digital values corresponding to the ports AN1-5. Unlike the standard SIP, which contains