Pioneer 2 / PeopleBot

Pioneer 2 Operating System

number of bytes you request via the GETAUX command—up to 200 bytes at a time.

P2OS waits to collect the requested number of incoming AUX-port serial bytes before

sending the GETAUX packet to the client. Use the GETAUX command with a zero

argument to flush the P2OS circular buffer and reset its pointers.

In the code example above, a fictitious command gets sent to a serial device attached

to the microcontroller's AUX port and retrieves a 10-byte response from that device (note

that ellipses mark the many portions of a complete client that have been deleted for

brevity).

ENCODERpac and ENCODER Command

Issue the ENCODER command #19 with an argument of 1 for a single or with an argument

of 2 or more for a continuous stream of ENCODERpac (type 144; 0x90) SIPs. Discontinue

the packets by sending the ENCODER command #19 with the argument 0.

Table 8. P2OS Encoder Server Information Packet Contents

Header integer Exactly 0xFA, 0xFB

Byte Count byte Number of data bytes + 2 (checksum)

Left Encoder integer Least significant, most significant portion of the

integer current 4-byte raw encoder count from the left drive wheel

Right Encoder integer Least significant, most significant portion of the

integer current 4-byte raw encoder count from the left drive wheel

Checksum integer Checksum for packet integrity

GRIPPERpac and GRIPREQUEST

To ameliorate a few shortcoming when we transferred connection and control of the P2

Gripper accessory from User I/O to the General I/O bus, P2OS 1.E introduced and we

improved the new GRIPPERpac (type=224; 0xE0) packet type and related GRIPREQUEST

P2OS command #37 in P2OS 1_F.

Table 9. Gripper packet contents (P2OS 1_F and later)

Header integer Exactly 0xFA, 0xFB

Byte Count byte Number of data bytes + 2 (checksum)

Type byte Packet type = 0xE0

HasGripper byte Gripper type: 0=none; 1=User; 2=General I/O

Grip_state byte See Table 12 and P2 Gripper Manual

Grasp_Time byte See P2 Gripper Manual

Checksum integer Computed checksum

Normally disabled, your client program must request one (command argument 1) or a

continuous stream (command argument > 1) of Gripper packets. Send GRIPREQUEST

with the argument value 0 to stop continuous packets.

PLAYLISTpac and PLAYLIST Command

Unlike its Pioneer and PeopleBot cousins, the AmigoBot mobile robot has onboard sound

reproduction hardware and software that includes a playlist of contents. To support the

ActivMedia Robotics Basic Suite that includes all ActivMedia’s robots, we’ve added the

PLAYLISTpac (type = 208; 0xD0) and PLAYLIST request command #91 to P2OS 1.E. We

document the command and packet here for completeness, but they have no effect

on the operation or performance of your Pioneer 2 or PeopleBot Mobile Robot.