Irobot Create Open Interface Sensor Packets - iRobot CREATE - OPEN INTERFACE Manual

iRobot Create Open Interface
Sensor Packets
Create sends back one of 43 different sensor data packets,
depending on the value of the packet data byte, when
responding to a Sensors command, Query List command,
or Stream command's request for a packet of sensor data
bytes. Some packets contain groups of other packets.
Some of the sensor data values are 16 bit values.
Most of the packets (numbers 7 – 42) contain the value of
a single sensor or variable, which can be either 1 byte or 2
bytes. Two-byte packets correspond to 16-bit values, sent
high byte first.
Some of the packets (0-6) contain groups of the single-
value packets.
Wait Event: Unsigned Equivalent of Inverse
Group Packet ID Packet Size
0 26 bytes
1 10 bytes
2 6 bytes
3 10 bytes
4 14 bytes
5 12 bytes
6 52 bytes
Bumps and Wheel Drops Packet ID: 7
The state of the bumper (0 = no bump, 1 = bump) and wheel
drop sensors (0 = wheel raised, 1 = wheel dropped) are sent
as individual bits.
Range: 0 - 31
Bit 7 6 5 4
Wheeldrop
Sensor n/a n/a n/a
Caster
Wall Packet ID: 8
The state of the wall sensor is sent as a 1 bit value
(0 = no wall, 1 = wall seen).
Range: 0 – 1
Cliff Left Packet ID: 9
The state of the cliff sensor on the left side of Create is
sent as a 1 bit value (0 = no cliff, 1 = cliff).
Range: 0 – 1
iRobot Create Open Interface (OI) Specification
Contains packets
7 - 26
7 - 16
17 - 20
21 - 26
27 - 34
35 - 42
7 - 42
Data Bytes: 1
unsigned
3 2 1
Wheeldrop Wheeldrop Bump
Left Right Left
Data Bytes: 1
unsigned
Data Bytes: 1
unsigned
Cliff Front Left
The state of the cliff sensor on the front left of Create is
sent as a 1 bit value (0 = no cliff, 1 = cliff).
Range: 0 – 1
Cliff Front Right
The state of the cliff sensor on the front right of Create is
sent as a 1 bit value (0 = no cliff, 1 = cliff)
Range: 0 – 1
Cliff Right
The state of the cliff sensor on the right side of Create is
sent as a 1 bit value (0 = no cliff, 1 = cliff)
Range: 0 – 1
Virtual Wall
The state of the virtual wall detector is sent as a 1 bit value
(0 = no virtual wall detected, 1 = virtual wall detected).
Note that the force field on top of the Home Base also trips
this sensor.
Range: 0 – 1
0
Low Side Driver and
Wheel Overcurrents
Bump
Right
The state of the three Low Side driver and two wheel
overcurrent sensors are sent as individual bits (0 = no
overcurrent, 1 = overcurrent).
Driver
LD0
LD1
LD2
Wheels
Range: 0 - 31
Bit 7 6
Motor
n/a n/a n/a Left Wheel Right Wheel LD-2
Packet ID: 10
Packet ID: 11
Packet ID: 1
Packet ID: 13
Packet ID: 14
Current Limit
0.5A
0.5A
1.6A
1.0A
5 4 3 2
Data Bytes: 1
unsigned
Data Bytes: 1
unsigned
Data Bytes: 1
unsigned
Data Bytes: 1
unsigned
Data Bytes: 1
unsigned
1 0
LD-0 LD-1
17