Honeywell HG1120 User manual

HG1120 INERTIAL
MEASUREMENT UNIT (IMU)
Installation and Interface Manual

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Honeywell Industrial Inertial Measurement Units
Electrical Interface
Mode and Communication Selection
Asynchronous Protocol
SPI Protocol
CAN 2A/2B Protocol
Mechnical Drawing and Installation
Export Guidance
Contact Us
Table of Contents
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Table 1. Connector Pin Description
Table 2. Mode Selection
Table 3. Control Message (0x04 Data Format)
Table 4. Main Status Word Definition
Table 5. Multiplexed Status Word
Table 6. Gyro and Accelerometer BIT Status
Table 7. Processor/Memory BIT Status Word
Table 8. Inertial Message (0x05 Data Format)
Table 9. Asynchronous Control Message (0x0C Data Format)
Table 10. Asynchronous Inertial Message (0x0D Data Format)
Table 11. SPI Control Message (0x04 Data Format)
Table 12. SPI Inertial Message (0x05 Data Format)
Table 13. SPI Control Message (0x0C Data Format)
Table of Tables

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Table 14. SPI Inertial Message (0x0D Data Format)
Table 15. CAN Control Message 1 Format
Table 16. CAN Control Message 2 Format
Table 17. CAN Control Message 3 Format
Table 18. CAN Inertial Message 1 Format
Table 19. CAN Inertial Message 2 Format
Table 20. CAN Inertial Message 3 Format
Table of Tables

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Honeywell Industrial Inertial
Measurement Units
Honeywell produces No License Required (NLR) Inertial Measurement Units (IMU) for industrial
applications including agricultural vehicles, robotics, survey, mapping, and stabilized systems.
These IMUs are designed for industrial application and can be used on air, land, and sea.
Honeywell began producing gyros in the 1940’s for the Honeywell C-1 autopilot and specifically
began producing MEMS gyros and accelerometers in the early 2000’s. Honeywell’s IMUs
utilize proprietary Honeywell technology and leverage existing production and engineering
infrastructure. Honeywell has deep and long lasting relations with many commercial customers
and is carrying that philosophy and product pedigree into our NLR IMU line. Honeywell’s forward
looking product strategies ensure that our NLR IMUs fit your current and future needs.
The HG1120 IMU is a device which measures angular rates, linear accelerations, and magnetic
fields in a body mounted strap down configuration. The IMU provides compensated incremental
angle and velocity data for navigation as well as angular rates and linear accelerations for
control. The data is reported through a digital serial interface bus and is available in a variety
of serial formats. The unit contains MEMS gyroscopes and accelerometers as well as the
electronics and software necessary to deliver precision control and navigation information.
The input axes form a right handed frame aligned with the IMU mounting frame.

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Electrical Interface
The pin assignments of the external system connector are shown below. Logic 0 corresponds
to the CMOS “low” logic state. Logic 1 corresponds to the CMOS “high” logic state.
Table 1. Connector Pin Description
PIN # SIGNAL NAME INPUT/OUTPUT & SIGNAL TYPE SIGNAL FUNCTION
1DIO3 Input - Device Configuration
CMOS compatible logic
No connect results in Logic 1. Active low for logic 0.
2DIO4 Input – Device Configuration
CMOS Compatible Logic
No connect results in Logic 1. Active low for logic 0.
3SPI_SCLK Input
CMOS Compatible Logic
SPI Clock
4SPI_MOSI Input
CMOS Compatible Logic
SPI Master Out Slave In (MOSI) data.
5SPI_MISO Output
CMOS Compatible Logic
SPI Master In Slave Out (MISO) data
6SPI_SS Input
CMOS Compatible Logic
SPI Slave Select (chip select), Default high, Active
low
7DIO1 Input – Device Configuration
CMOS Compatible Logic
No connect results in Logic 1. Active low for logic 0.
8RESET_N Input – Device Configuration
CMOS Compatible Logic
Logic 0 applied for 15 milli-seconds will stop all
processing. Upon logic 1, the IMU will restart as
if power had been removed and re-applied. No
connection is required.
9DATA _RDY Output
CMOS Compatible Logic
Data Ready on Rising Edge to Logic 1.
@ Logic 1, maximum 500 micro-seconds.
10 DIO2 Input - Device Configuration
CMOS Compatible Logic
No connect results in Logic 1. Active low for logic 0.
11,12 VDD Input Power (3.0 – 5.5 VDC) The input voltage should monotonically increase at
start with ripple < 30 mV P-P. The device draws < 0.4
Watts and 125 mA.
13 PWR_RTN Power Return Return path for input power.
14 DGND Signal Return Use this pin to reference digital signals.
15 PWR_RTN Power Return Return path for input power.
16 SER_DATA_OUT_H Output RS-422 Asynchronous High
17 No Connect N/A N/A
18 SER_DATA_OUT_L Output RS-422 Asynchronous Low
1921 No Connect
22 CAN_L Bi-directional - ISO 11898-2 Can Bus Low
23 No Connect No Connect
24 CAN_H Bi-directional - ISO 11898-2 Can Bus High

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Mode and Communication Selection
The HG1120 supports the message protocols, data rates, and bandwidths, described in Table 2.
The HG1120 can be configured by setting discrete inputs DIO1 through DIO4. These pins are only
read upon reset or power up. State of the pins is shown in word 9 of the multiplexed status word.
The first frame of serial output data after power-application will contain a fixed pattern of 0x55s in
place of sensor data. Subsequent frames of serial output data will contain compensated sensor data.
The control bandwidth in Table 2 describes the nominal - 90° phase point. The -3dB frequency
is nominally 2x the -90° phase frequency. The bandwidth is exclusive of transmission delay.
Control data consists of the angular rates, linear acceleration, magnetic, and IMU status words in
message set {0x04, 0x05} and set {0x0C, 0x0D}. The angular and linear data is filtered and sampled
at 1800 Hz. The 1800 Hz filtered angular and linear data is decimated for 600 Hz control data.
The 300/100 Hz navigation data output consists of incremental (or “delta”) angles and velocities
as shown in message IDs 0x05 and 0x0D. The navigation data is unfiltered 1800 Hz sensor data
which is summed to the navigation data rate (300 Hz or 100 Hz). Accurate attitude and position
calculations require that all messages be received and used.
Gyro and accelerometer residuals are calculated and carried forward to the next message for both
navigation and control data. The serial output FIFO is loaded with the LS byte first and LS 16-bit
word first. The sensor data (gyro, accelerometer, magnetometer, and temperature) are all signed 2’s
complement integers.

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Table 2. Mode Selection
DIO4 DIO3 DIO2 DIO1 PROTOCOL CONTROL/NAV.
DATA RATES
CONTROL/INERTIAL
MESSAGE FORMATS
CONTROL DATA
BANDWIDTH
(90° PHASE POINT)
11 1 1 ASYNC 1800/300 Hz 0x04/0x05 97 Hz Gyro
155 Hz Accelerometer
11 1 0 ASYNC 600/100 Hz 0x0C/0x0D
11 0 1 ASYNC 600/100 Hz 0x0C/0x0D 90Hz
11 0 0 ASYNC 600/100 Hz 0x0C/0x0D 50Hz
10 1 1 SPI 1800/300 Hz 0x04/0x05 97 Hz Gyro
155 Hz Accelerometer
10 1 0 SPI 600/100 Hz 0x0C/0x0D
10 0 1 SPI 600/100 Hz 0x0C/0x0D 90Hz
10 0 0 SPI 600/100 Hz 0x0C/0x0D 50Hz
01 1 1 CAN2A 600/100 Hz 11 Bit ID 90Hz
01 1 0 CAN2A 600/100 Hz 11 Bit ID 50Hz
01 0 1 CAN2B 600/100 Hz 29 Bit ID 90Hz
01 0 0 CAN2B 600/100 Hz 29 Bit ID 50Hz
00 1 1 SPARE NA NA NA
00 1 0 SPARE NA NA NA
00 0 1 SPARE NA NA NA
00 0 0 SPARE NA NA NA
Asynchronous Protocol
The asynchronous 1800/300 Hz data protocol is as specified in Table 3 – Control Message (0x04)
Format and Table 7 – Inertial Message (0x05) Format.
The asynchronous 600/100 Hz data protocol is as specified in Table 8 – Control Message (0x0C)
Format and Table 9 – Inertial Message (0x0D) Format.
The transmit baud rate will be 1Mbits/sec with 1 start bit, 8 data bits, 1 stop bit, and no parity.

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Table 3. Control Message (0x04 Data Format)
POSITION PARAMETER LENGTH
(BYTES)
LSB WEIGHT UNITS OR CONTENTS
1 IMU Address 1 N/A Constant 0x0E
2 Message ID 1 N/A Constant 0x04
3 Angular Rate X 2 2 -20 * 1800 * 2/3 rad/sec/LSB
4 Angular Rate Y 2 2 -20 * 1800 * 2/3 rad/sec/LSB
5 Angular Rate Z 2 2 -20 * 1800 * 2/3 rad/sec/LSB
6 Linear Acceleration X 2 2 -14 * 1800 * 2/3 0.3048 meters/sec2/LSB
7 Linear Acceleration Y 2 2 -14 * 1800 * 2/3 0.3048 meters/sec²/LSB
8 Linear Acceleration Z 2 2 -14 * 1800 * 2/3 0.3048 meters/sec²/LSB
9 Mag Field X 2 0.438404 Milli-gauss/LSB
10 Mag Field Y 2 0.438404 Milli-gauss/LSB
11 Mag Field Z 2 0.438404 Milli-gauss/LSB
12 Main Status Word 2 N/A See Table 4.
13 Multiplexed Status Word 2 N/A See Table 5.
14
Checksum
Sum of all message data
(positions 1…13 of this
table), taken as 16 bit
words, and summed
without regard for rollover.
2N/A
// this pseudo code illustrates the
checksum algorithm
u16sum = 0;
for (i=0; i<12; i++) // (26-2)/2=12
{ u16sum += u16_msg_array[i]; }
Checksum = u16_msg_array[12];
if (Checksum != u16sum) {checksum
error}
Total Length 26
Table 4. Main Status Word Definition
BIT(S) PARAMETER VALUES
0-3 Multiplexed Status Word Counter See Table 5.
4 IMU OK 0=OK, 1=Failed
5 Sensor Board Initialization Successful 0=OK, 1=Failed
6 Accelerometer X Validity 0=OK, 1=Failed
7 Accelerometer Y Validity 0=OK, 1=Failed
8 Accelerometer Z Validity 0=OK, 1=Failed
9 Gyro X Validity 0=OK, 1=Failed
10 Gyro Y Validity 0=OK, 1=Failed
11 Gyro Z Validity 0=OK, 1=Failed
12 Magnetometer Validity 0=OK, 1=Failed
13 Power Up BIT Status (Latched) 0=OK, 1=Failed
14 Continuous BIT Status (Latched) 0=OK, 1=Failed
15 Power Up Test - Sets at start of serial data (~100
milliseconds) and clears before 300 milliseconds. 0=Normal, 1+Power Up Tests

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Table 5. Multiplexed Status Word
MUX WORD COUNTER CONTENTS (16 BITS) UNITS
0 Software Version Number Binary
1 Gyro and Accelerometer Status See Table 6
2Gyro and Accelerometer BIT History (Latched Until Power
is Cycled or Unit is Reset)
Bits 3-8 of Mux Word Counter 1 will be latched if the
individual BIT test counter reaches 15. The test counter
is increased by 1 for a failure and then reduced by 1 if
the failure clears. Bit 2 of Mux Word Counter 1 employs
similar logic but the test counter limit is 5.
3 Magnetometer BIT Status Bits 3-15 are Honeywell use only.
0=OK, 1=Failed, applies to remaining bits.
4 Reserved Reserved
5 Processor/Memory BIT Status See Table 7
6Processor/Memory BIT Status (Latched Until Power is
Cycled or Unit is Reset) See Table 7
7 Accelerometer/Gyro Sensor Temperature ~0.0039 °C/LSB, Not Calibrated
8 Magnetometer Temperature ~0.0039 °C/LSB, Not Calibrated
9 DIO1-DIO4 Device Configuration Echo
Bit 0: DIO 1
Bit 1: DIO 2
Bit 2: DIO 3
Bit 3: DIO 4
Bit 4-15: reserved
10-15 Reserved 0
Table 7. Processor/Memory BIT Status Word
Table 6. Gyro and Accelerometer BIT Status
BIT(S) PARAMETER VALUES
0 Loop Completion Test 0=OK, 1=Failed
1 RAM Test 0=OK, 1=Failed
2 Coefficient Table CRC Test 0=OK, 1=Failed
3 Configuration Table CRC Test 0=OK, 1=Failed
4 Normal Mode SW CRC Test 0=OK, 1=Failed
5 Spare 0=OK, 1=Failed
6 Stack Overflow Test 0=OK, 1=Failed
7 Watchdog Timer Test 0=OK, 1=Failed
8Processor Test 0=OK, 1=Failed
9-15 Reserved N/A
BIT(S) PARAMETER VALUES
0 Sensor Electronics 0=OK, 1=Failed
1 Sensor Data Ready 0=OK, 1=Failed
2 Temperature 0=OK, 1=Failed
3-5 Accelerometer X, Y, Z Health 0=OK, 1=Failed
6-8 Gyro X, Y, Z Health 0=OK, 1=Failed
9-15 Reserved 0=OK, 1=Failed

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Table 8. Inertial Message (0x05 Data Format)
POSITION PARAMETER LENGTH
(BYTES)
LSB WEIGHT UNITS OR CONTENTS
1 IMU Address 1 N/A Constant 0x0E
2 Message ID 1 N/A Constant 0x05
3-13 Control Data 22 N/A Contents same as Message 0x04
Positions 3-13.
14 Delta Angle X 4 2-34
radians/LSB
or equivalently,
radians/second/Hz/LSB
15 Delta Angle Y 4 2-34
16 Delta Angle Z 4 2-34
17 Delta Velocity X 4 2-28
0.3048 meters/sec/LSB
or equivalently,
0.3048 meters/sec2/Hz/LSB
18 Delta Velocity Y 4 2-28
19 Delta Velocity Z 4 2-28
20 Checksum
Sum of all message data (positions
1-19 of this table), taken as 16 bit
words, and summed without regard for
rollover.
2N/A // this pseudo code illustrates the
checksum algorithm
u16sum = 0;
for (i=0; i<24; i++) // (50-2)/2=24
{ u16sum += u16_msg_array[i]; }
Checksum = u16_msg_array[24];
if (Checksum != u16sum) {checksum
error}
Total 50
Table 9. Asynchronous Control Message (0x0C Data Format)
POSITION PARAMETER LENGTH
(BYTES)
LSB WEIGHT UNITS OR CONTENTS
1 IMU Address 1 N/A Constant 0x0E
2 Message ID 1 N/A Constant 0x0C
3 Angular Rate X 2 2-20 * 600 rad/sec/LSB
4 Angular Rate Y 2 2-20 * 600 rad/sec/LSB
5 Angular Rate Z 2 2-20 * 600 rad/sec/LSB
6 Linear Acceleration X 2 2-14 * 600 0.3048 meters/sec2/LSB
7 Linear Acceleration Y 2 2-14 * 600 0.3048 meters/sec2/LSB
8 Linear Acceleration Z 2 2-14 * 600 0.3048 meters/sec2/LSB
9 Mag Field X 2 0.438404 Milli-gauss/LSB
10 Mag Field Y 2 0.438404 Milli-gauss/LSB
11 Mag Field Z 2 0.438404 Milli-gauss/LSB
12 Main Status Word 2 N/A See Table 4
13 Detailed Multiplexed Status Word 2 N/A See Table 5
14 Checksum
Sum of all message data (positions
1-13 of this table), taken as 16 bit
words, and summed without regard for
rollover.
2N/A // this pseudo code illustrates the
checksum algorithm
u16sum = 0;
for (i=0; i<12; i++) // (26-2)/2=12
{ u16sum += u16_msg_array[i]; }
Checksum = u16_msg_array[12];
if (Checksum != u16sum) {checksum
error}
Total Length 26