Host-to-aux serial transfers, Encoder packets, Gripper packets – Pioneer 2TM User Manual
Page 51: Ncoder packets
ActivMedia Robotics
For auto-baud, the HOST serial port automatically reverts to its FLASH default baud rate if,
after being reset by the HOSTBAUD client command, it does not receive a subsequent
and valid client-command packet within 500 milliseconds.
HOST-to-AUX Serial Transfers
Use the client-side TTY2 command #42 with a string argument to have that string sent
out the AUX1 port to the attached serial device, such as a robotic camera. Similarly, use
the TTY3 command #66 to send a string argument to the AUX2 port.
AROS also maintains two circular buffers for incoming serial data from the AUX1 and
AUX2 ports. On request, AROS sends successive portions of the buffers to your client via
the HOST port in the respective SERAUXpac (type = 176; 0xB0) and SERAUX2pac (type =
184; 0xB8) SIPs. Use the GETAUX command 43 for AUX1 or GETAUX2 command number 67
for AUX2. Use the integer argument value of zero to flush the contents of the respective
buffer. Use an argument value of up to 253 bytes to have AROS wait to collect the
requested number of incoming AUX-port serial bytes and them send them in the
respective SERAUXpac or SERAUX2pac SIP.
E
NCODER PACKETS
Issue the ENCODER command #19 with an argument of one for a single, or with an
argument value of two or more for a continuous stream of ENCODERpac (type 144; 0x90)
SIPs. Discontinue the packets with the ENCODER command #19 with an argument of
zero.
Table 9. ENCODERpac SIP 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 accumulated encoder counts from the left wheel
Right Encoder
integer
Least significant, most significant portion of the
integer
current accumulated encoder counts from the left wheel
Checksum integer Checksum
for packet integrity
Gripper packets
AROS controls the Gripper accessory for the Pioneer and Performance PeopleBot robots.
The client sends commands to the Gripper servers and gets Gripper status information
from the standard SIP. Please consult the respective manuals for details.
Table 10. GRIPPERpac packet contents
HEADER
int
Exactly 0xFA, 0xFB
BYTE COUNT
byte
Number of data bytes + 2 (checksum)
TYPE
byte
Packet type = 0xE0
H
AS
G
RIPPER
byte
Gripper type: 0=none; 1=User; 2=PeopleBot
GRIP
_
STATE
byte See
nearby Table
GRASP
_T
IME
byte
MS time controls grasping pressure
CHECKSUM
integer
Computed
checksum
AROS supports a GRIPPERpac (type=224; 0xE0) packet type and related GRIPREQUEST
P2OS command #37 to retrieve setup and status information from the servers.
Normally disabled, your client program may request one or a continuous stream
(command argument > one) of Gripper packets. Send GRIPREQUEST with the
argument value zero to stop continuous packets.
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