Omega i-SERIES User Manual

Example of CRC calculation in “C” language
This subroutine used to do CRC calculation
#define POLY 0xA001;
unsigned int crc_calculation (unsigned char *start_string, unsigned char number_byte)
{
unsigned int crc;
unsigned char bit_counter;
unsigned char *data_pointer;
data_pointer= start_string;
crc = 0xffff; // Initialize crc
while (number_byte>0)
{
crc ^= data_pointer // crc XOR with data
bit_counter=0; // reset counter
while (bit_counter < 8)
{
if (crc & 0x0001)
{
crc >>= 1; // shift to the right 1 position
crc ^= POLY; // crc XOR with POLY
}
else
{
crc >>=1; // shift to the right 1 position
}
bit_counter++; // increase counter
}
number_byte--; // adjust byte counter
}
return (crc); // final result of crc
}
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Omega i-SERIES Specifications

General

Category	Controller
Manufacturer	Omega
Series	i-SERIES
Communication Interface	RS-232, RS-485, Ethernet
Operating Temperature	0 to 50°C (32 to 122°F)

Summary

PART 3 HARDWARE

3.1 Communication Interfaces

Describes RS-232 and RS-485 communication interfaces.

3.2 Wiring RS-232 Interface

Details the wiring for the RS-232 interface.

3.3 Wiring RS-485 Interface

Explains the wiring for the RS-485 interface.

PART 4 COMMUNICATION SETUP

4.1 Flow Chart

Visualizes the communication setup options and parameters.

4.2 Setup the i-Series Device Through the Front Panel

Guide to configuring the device using its front panel buttons.

4.3 Abbreviations, Range, Default Setup

Explains abbreviations, ranges, and default settings for communication.

Abbreviations, Range, Default Setup Continued

Continues the explanation of communication parameters and their settings.

Communications Parameters Submenu

Allows adjustment of serial communication settings for device compatibility.

Bus Format Submenu

Determines communication standards and data formats for the serial bus.

PART 5 i-SERIES PROTOCOL

5.1 Command Structure

Explains the structure of commands for reading and writing data.

5.2 Command Formats

Details the command formats for various i-Series devices and modes.

5.3 Response Format

Shows response formats with and without ECHO mode.

5.4 Error Message

Lists possible error messages and their codes transmitted to the host computer.

5.7 Command Formats

Details command formats, assuming asterisk recognition character and RS-232 communication.

5.7.1 Input Type (Command Index 07)

Explains the format for setting the input type for different instruments.

5.7.2 Reading Configuration: (Command Index 08)

Details the format for configuring reading parameters like decimal points and filters.

5.7.10 Communication Parameters (Command Index 10)

Explains parameters for setting baud rate, parity, data bits, and stop bits.

5.7.11 Bus Format (Command Index 1F)

Configures bus format, including separator, mode, standard, and echo settings.

5.7.12 Data Format (Command Index 20)

Configures data format for commands like V01 or continuous mode.

5.7.15 Reading Scale and Offset (Command Indexes 14 and 3A)

Explains how to set reading scale and offset for accurate data display.

Scaling

Illustrates the Y=mx+b formula for scaling and provides calculation examples.

Calculate Scale

Details the process of calculating and encoding scale factors.

Calculate Offset

Details the process of calculating and encoding offset factors.

PART 6 MODBUS PROTOCOL

6.7 Modbus RTU Registers

Lists the Modbus registers supported by i-Series devices and their ranges.

6.8 Command Format

Outlines the formats for sending and receiving Modbus commands.

6.8.1 Read Multiple Register (03 or 04)

Details the command format for reading multiple registers.

6.8.2 Write to Single Register (06)

Explains the command format for writing a parameter to a single register.

APPENDIX A

Reading Scale and Offset for Process/Strain Gage Instrument

Details setting reading scale and offset for specific instruments with linearization.