-54-
Temperature =
252.55 C
-> IEEE-754 Reverse Representation =
437C8CCC
Temperature Reading at register locations 0000h-0001h:
Address
Data
0000h
437Ch
0001h
8CCCh
The pyrometer temperature and current values are available at multiple register addresses. For example,
the temperature reading is mapped at both 0x0000-0x0001 and 0x0006-0x0007. These redundant
mappings provide the ability to read more than one reading using a single Modbus message. For
example, the currents for both Channel 1 and Channel 2 can be obtained by reading two floating point
values starting at register address 0x0012.
You can find the address for each value in the Modbus Register Address Map, located at the end of this document.
Pyrometer Name String
The pyrometer name consists of a string of up to 32 ASCII bytes in length which can be accessed at
addresses 1100h-111Fh. The pyrometer is shipped with the name string configured to the unit’s serial
number.
To read the name string, start at 1100h and read the ASCII values of the name string at sequential
register addresses until a character with the null value (0x00) is encountered. The null character delimits
the end of the string.
To write the name string, begin at 1100h and sequentially write the ASCII values for each character in the
new name string to sequential register addresses. Once the string of characters has been written to the
register locations the “Save” command must be executed using the Command Register in order to make
the change permanent. (See the “Command Register” section below).
Calibration Factors and Tables
Calibration factors and table entries are accessed at register address block 2000h-3FFFh (see the
Modbus Register Address Map). All are 32-bit floating point values with the exception of the sizes for the
Emissivity, Fit, and Average/Bandwidth Tables which only occupy 1 register location.
IMPORTANT NOTE
: Changing the Emissivity, Fit or Averaging tables requires that table entries are
written first, followed by a register write to update the table size.
Command Register
The pyrometer Command Register at Modbus address 8000h provides a way to save changes made to
the pyrometer settings and also allows the user to initiate a soft reboot of the pyrometer. Changes to the
pyrometer parameters can be saved to EEPROM by writing 7001h to the Command Register. A
pyrometer soft reboot can be initiated by writing 8080h to the Command Register.
Command Register Function Codes
Function Code
Description
7001h
Save to parameters to EEPROM
8080h
Soft Reboot
Configuration Registers
The pyrometer has two configuration registers, GenConfigReg1 and GenConfigReg2. The individual bits of these
registers can be accessed to query or change the pyrometer’s mode configuration. These registers can be read and
written as 16 bit values using Modbus functions 03h and 06h, or the individual bits can be read/written using
Modbus functions 01h and 05h.
A mode is enabled by writing a ‘1’ to the corresponding configuration bit.
