ActivMedia Robotics
Normally enabled (default was disabled in P2OS), change E_STALL by sending the AROS command #56. With argument of zero, E_STALL gets disabled. An argument value of one
ACCESSORY COMMANDS AND PACKETS
Several types of alternative server information packets (SIPs) come with AROS to better support the ActivMedia Robotics community. On request from the client by a related AROS command, the AROS server packages and sends one or a continuous stream of information packets to the client over the HOST serial communication line. Extended packets get sent immediately after the standard SIP that AROS sends to your client every SIP milliseconds (typically 100).22
The standard SIP takes priority and gets sent as soon as the communication port is free and the cycle timer expires. So you may have to adjust the communications baud rate to accommodate all data packets in the allotted cycle time, or some packets may never get sent.
Packet Processing
Identical with the standard SIP, all AROS server information packets get encapsulated with a header (0xFA, 0xFB), byte count, packet type byte, and trailing checksum. It is up to the client to parse the packets, sorted by type for content. Please consult the respective client application programming manuals for details.
ARIA, for example, comes with a framework for packet parsing and has an internal parser for the PSOS/P2OS/AROS packet type 0x3S
Table 8. CONFIGpac contents (AROS v1.5 and later)
LABEL | DATA | DESCRIPTION | |
HEADER | int | Common packet header = 0xfAFB | |
TYPE | byte | IDs ENCODERpac = 0x20 | |
BYTE COUNT | byte | Number of following data bytes | |
ROBOT TYPE | str | Typically “Pioneer” | |
SUBTYPE | str | Identifies the ActivMedia robot model; e.g. “p3dx”, | |
SERIALNUM | str | Serial number for the robot. | |
4MOTS | byte | Antiquated (=1 if AT with P2OS) | |
ROTVELTOP | int | Maximum | rotational velocity; deg/sec |
TRANSVELTOP | int | Maximum | translation speed; mm/sec |
ROTACCTOP | int | Maximum | rotation (de)acceleration; deg/sec2 |
TRANSACCTOP | int | Maximum | translational (de)acceleration; mm/sec2 |
PWMMAX | int | Maximum | motor PWM (500=fully on). |
NAME | str | Unique name given to your robot. | |
SIP | byte | Server information packet cycle time | |
HOSTBAUD | byte | Baud rate for | |
|
| 2=38.4k, | 3=56.8k, 4=115.2k. |
AUXBAUD | byte | Baud rate for AUX serial port 1; see HostBaud | |
GRIPPER | int | 0 if no | Gripper; else 1 |
FRONT SONAR | int | 1 if robot has front sonar array enabled, else 0 | |
REAR SONAR | byte | 1 if robot has rear sonar enabled, else 0 | |
LOWBATTERY | int | In 1/10 | volts; alarm activated when battery charge falls |
|
| below this value. | |
REVCOUNT | int | Current | number of differential encoder ticks for a 360 |
|
| degree revolution of the robot. | |
WATCHDOG | int | Ms time | before robot automatically stops if it has not |
22You may have to adjust the HOST serial baud rate to accommodate the additional communications traffic.
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