Honeywell HPB User manual

Honeywell Precision Barometer
HPB & HPA
Users Manual
Version H2.4
ADS-14071 5/02 Solid State Electronics Center

ADS-14071 Rev. 5/02
Customer Service Representative
(800) 2 -8295 fax: (76 ) 954-2257
E-Mail: ssec.customer[email protected]
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Honeywell reserves the right to make changes to any products or technology herein to improve reliability, function
or design. Honeywell does not assume any liability arising out of the application or use of any product or circuit
described herein; neither does it convey any license under its patent rights nor the rights of others.
© opyright 2001 Honeywell Inc., All rights reserved. Printed in U.S.A.

i
Table of Contents
1.0 INTRODU TION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Hardware Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
2.0 GETTING STARTED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.2 Equipment Needed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.3 Terminal Program Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2.4 Initial Turn-On Response. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.5 ommand Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.6 Step-By-Step Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.7 ommand Functional Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.0 OMMANDS - QUI K REFEREN E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4.0 FUN TIONAL OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.2 What Is Integration? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.3 Pressure Reading ontrol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4 ustomized Pressure Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.5 ommand Illustrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.6 Pressure Reading Decimal Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
4.7 HPB Addressing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
5.0 OMMANDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.1 ommand Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.2 Information Request ommands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
5.3 Action Directing ommands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.4 ommand RepliesGeneral . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
5.5 AS II Format Replies. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
5.6 Binary Format Replies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
5.7 ommand And Reply Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
5.8 ommand Errors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
5.9 ommand Summary Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
5.10 ommand Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
6.0 ELE TRI AL ONNE TIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
7.0 TIMING DIAGRAMS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
8.0 SPE IFI ATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
9.0 DIMENSIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

ii
Figures
Figure 1. HPB Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Figure 2. Pressure Reading ontrol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Figure 3. ustom Slope (X=) Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 4. ustom Offset (Z=) Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Figure 5. Integration (I=) ommand, Example 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 6. Integration (I=) ommand, Example 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Figure 7a. Deadband and Sensitivity (DS) ommand Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 7b. Deadband and Sensitivity (DS) ommand Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 8. Idle ount (I ) ommand Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Figure 9. Synchronize Integration ycles (SI) ommand Example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Figure 10. HPB Ring Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Figure 11. HPB Multi-drop Network . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 12. Single HPB ommand and Reply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 13. Multiple HPB Network ommand and Replies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 14. HPB Electrical onnector Pin Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Figure 15. onnection to a Host omputer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Figure 16. Default Single Pressure Reading Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Figure 17. Default ontinuous Pressure Reading Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Figure 18. ontinuous Pressure (with I = 1) Timing Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Figure 19. Timing Diagram for 20 Readings Per Second . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Figure 20. Timing Diagram for 50 Readings Per Second . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Figure 21. Timing Diagram for 120 Readings Per Second . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Figure 22. HPB ase Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Figure 23. Electrical onnector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60

iii
Tables
Table 1. Decimal Place Locations for Pressure Readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Table 2. Header Description for Binary Format Pressure Readings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Table 3. Binary Format haracter odes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 4. ommand List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Table 5. ommand Factory Default List . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Table 6. Display Units Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 7. Transmission Times at Selected Baud Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Table 8. Number of bytes in Various Replies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Table 9. AS II onversion Table, Decimal to Hexadecimal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Table 10. RS-232 Standard Pin onnections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61

1
1.0 INTRODUCTION
1.1 Product Overview
The Honeywell Precision Barometer* (HPB) provides high accuracy absolute pressure readings in digital form. The
first-time user will be able to use the HPB within minutes, yet capability exists to configure the HPB for optimum
performance in specific applications.
The heart of the HPB measuring system is a silicon piezoresistive sensor, which contains both pressure and
temperature-sensitive elements. Digital signals representing temperature and pressure are processed by a
microprocessor to produce fully temperature compensated and calibrated pressure readings over the entire -40 to
85° temperature range.
The HPB receives commands and sends data in either a ring or a multidrop TTL-Level configuration. Using an RS232-
to-TTL converter, up to 89 units can be connected in a ring or multi-drop configuration to a single serial port of a
computer. Group (multicast) addressing allows up to nine groups of HPBs to be addressed with a single
command. Global (broadcast) addressing will send a command to all HPBs on the bus.
Any computer having a serial port, terminal emulation software and a RS232-to-TTL converter can be connected to
the HPB to allow the user to select baud rates, sample rates, readout resolution, units of pressure and other choices.
User selected functions are set through the digital interface. The selected functions may either be used temporarily,
until the HPB is powered down, or may be stored in the internal EEPROM to automatically configure the HPB each
time power is applied.
The HPB is a low power device. It can be configured to enter a micropower shut down mode with a simple command
or by switching the state of power control line, see the OP command in section 5.10 for details. For buoy
applications, the HPB has a wave filtering routine to make data acquisition easier. See the DO command in section
5.10 for details.
1.2 Hardware Description
See Sections 8 and 9.
* For simplicity, references thoughout this manual to both HPB & HPA have been shortened to HPB.

2
2.0 GETTING TARTED
2.1 Overview
The first-time user should approach the HPB in a manner analogous to using a word processor program; i.e., many
features are available but one may begin by using those of interest at the moment. Section 2.7 of this manual lists
command features by functional groups to assist in this selection. When shipped from the factory, the default
settings provide a pressure transducer that will be usable for many applications. Feel free to make command-driven
configuration changes as you become familiar with the HPB. Default parameters are restored when the power is
cycled. Once the user is familiar with the performance and command structure, changes may be made and stored
using the Store Parameters (SP) command. Once stored, the new default settings are activated each time the HPB is
powered up. This tailors the personality of the HPB to meet the needs of a particular application.
2.2 Equipment Needed
To prepare the HPB for operation, several items are needed:
 A mating connector with proper wiring connections (see connector part number and wiring diagram in Section 6-
Electrical onnections);
 A D power supply;
 A pressure source;
 A computer, or host processor, having an RS-232 serial port and terminal program software such as PRO OMMTM,
VERSATERMTM, TERMINAL (Windows® 3.x) or HYPERTERMINAL (Windows® 95). These programs are normally
used to interface to a modem. The wiring diagram designates which HPB pins must connect to the computer
send, receive and common pins for proper communications. Some computers may not have an RS-232 serial
port connection identical to the one shown in Section 6, making it necessary to adapt the HPB connections to that
particular computer.
 An RS232-to-TTL converter
2.3 Terminal Program ettings
 Enter the following settings in the terminal program:
Baud Rate............................................................. 9600
Start Bits......................................................................1
Data Bits......................................................................8
Stop Bits......................................................................1
Parity....................................................................None
 Attach a line feed to the incoming carriage return < R>.
 Turn the local echo ON.
When shipped from the factory, the HPB is set to a baud rate of 9600, 1 start bit, 8 data bits with no parity and
one stop bit. If the baud rate has been subsequently changed, and is unknown, it will be necessary to search all
baud rate values to reestablish communication. See the BP command description in Section 5.10 of this manual
for possible settings.

3
2.4 Initial Turn-on Response
Digital Output
Once the wiring connections and terminal program settings are complete, the HPB will automatically send the
following response (or similar to) when power is applied. This reply will be generated any time power is applied to
the HPB.
Typical Reply:
?01HPB_ _ 1200HPAa ring network configuration
?00HPB_ _1200HPAa multi-drop network configuration
The ?01 or ?00 indicates a default address device called a null address. This HPB has not yet been assigned
an ID number so it assumes the null address.
2.5 Command Format
Any command interaction with the HPB requires electrical connection to the TTL serial communications pins.
There are two basic types of commands  action directing commands and information requesting commands.
Theses are described in ommands  Section 5
Typical HPB commands have the form *ddcc = nnn <cr>
Where: * is the command header character
dd is the decimal address of the HPB
cc is a command (refer to ommands  Section 5 for a complete description of commands)
= equal sign (required in some commands)
nnn additional characters (required in some commands)
<cr> carriage return is required to end all commands
(do not type, press the ENTER/RETURN key)
2.6 tep-by- tep Examples (Only for single HPB connection)
 READ INGLE PRE URE
Once the HPB is powered up and connected to a computer, enter the following command:
Type: *00P1 <cr> Response: ?01CP=15.458 (ring)
?00CP=15.458 (multi-drop)
Where: * indicates the start of a command
00 is the null address of the HPB (see note below)
P1 is the command to read the most current pressure
Note: The ? indicates a response from a null address HPB  one which has not been assigned a device ID. A
null address, 00, is coded into each HPB at the factory. When a ring networked null address HPB
responds, it adds one to its address, hence, the response 01. Refer to the ID command in Section 5.10
for a description of addresses and responses.
In the reply, the 01 identifies the individual unit address (range 01-89). The  P=15.458 indicates
a compensated pressure of 15.458 psi. Your unit may not show this specific reading, depending on the
applied pressure it is measuring.

4
 ET DEVICE ID
To give the HPB an assigned address of 01 up to 89, enter the following commands (Assumes the HPB is still null-
addressed):
Type: *00WE <cr> This enables the HPB to change a parameter in RAM
Type: *00ID=01 <cr> This sets the null addressed HPB to device ID=01.
Note: The device ID is now used in the command input
Type: *01 = <cr> Response: #01 =00052036 (serial number test)
The # now replaces the ? in the header and indicates the HPB response is from an address assigned unit.
Where: * indicates the start of a command
00 is the null address of the HPB
WE is the command to enable a configuration parameter change
ID is the command to change the device address
01 is the assigned HPB address for this example
S= is the command to read the serial number
 READ PRODUCTION DATE
To read the production date, enter the following command:
Type: *01P= <cr> Response: #01P=09/26/00
 READ CONTINUOU PRE URE
For continuous pressure readings at the factory set default rate of 5 per second, enter the following command:
Type: *01P2 <cr> This enables a continuous stream of compensated pressure readings
to flow into the terminal program.
Type: $*99IN <cr> This is the best way to stop the continuous pressure reading commands.
The $ character temporarily stops, or suspends, either the continuous
pressure or temperature readings. The *99IN command stops the continuous
readings.
 CHANGE TO A NEW AMPLE RATE
Enter the following command:
Type: *01WE <cr> This enables the HPB to change a parameter in RAM.
Type: *01I=M20<cr> This sets the integration time to value 20, which corresponds to an output
sample every 2 seconds.
The sample rate will change to one every 2 seconds. I= is an abbreviation for Integration time which determines
how long to accumulate pressure samples between readings. Each integration period gathers the data for one
pressure reading output (see Section 4.2 What is integration?). The range of integration times can be set by
specifying readings per second (I=R45 for 45 readings/sec) or time delay in 100 millisecond intervals (I=M60
for 6 seconds). The factory set integration time is 5 samples per second (I=M2). See Section 5.10, command
descriptions, for more detail.
The output data rate can also be altered by use of the idle count (IC) command or by changing the reading rate (RR)
command in conjunction with the operating mode (OP) command. See Section 4 for description of these commands.
 REPEAT THE READ CONTINUOU PRE URE TEP ABOVE
Notice the slower output rate of one sample every 2 seconds.

5
 TRY OTHER COMMAND
Experiment with other commands to become familiar with the command structures. A short overview of each command
with input and response examples is shown in Section 3 ommands  Quick Reference. See Section 5 ommands
for complete command descriptions. Until an P=ALL command is executed, no changes will be stored in the
EEPROM. ycle the power or send an IN=RE ET command to revert to previous EEPROM settings.
2.7 Command Functional Groups
 PRE URE DI PLAY UNIT HPB reads out psi, in wc, mm Hg, etc.
DU Set pressure units for output readingsany one of 17 units
U= Specify a user supplied unit of measure
 TEMPERATURE
T1 Single °
T2 ontinuous °
T3 Single °F
T4 ontinuous °F
 RING/MULTI-DROP BU PARAMETER
BP hanges baud rate and parity
ID Assign device ID and group addresses
M= Select alternate message Headers [Multi-Drop]
SI Synchronize Integration cycles among units [Multi-Drop]
TO Set Transceiver Operating parameters
 OUTPUT READING AND RATESpeed up or slow down output rate
Single Reading ommands
P1 Single pressure reading...AS II format
P3 Single pressure reading...binary format
T1 Single temperature reading...°
T3 Single temperature reading...°F
ontinuous Readings ommands
P2 ontinuous pressure readings...AS II format
P4 ontinuous pressure readings...binary format
T2 ontinuous temperature readings...°
T4 ontinuous temperature readings...°F
Integration Time ommands Changes pressure reading response time
DS Set deadband and sensitivity parameters
I= Set pressure integration time and reading rate
SI Synchronize pressure Integration cycles
Idle ount ommand Changes pressure reading response time
I Set number of idle integration cycles
Reading Response To hanges In Input PressureFilters small changes
RR Set number of identical readings to skip
OP Transmit all readings or only changed readings