Omega UWBT Series, User Manual

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11-1
Data Logging
11
Section 11 - Data Logging
11.1. Data Logging (LOG)
Data logging module is responsible for data recording into the EEPROM of the
UWBT device, the logged data is further made available for retrieving through
the USP (User Smart Phone) or PC for the End-User processing. This module
interacts directly with RTC & EADC drivers to obtain Date/Time stamp and
processed sensor data respectively. Thus stored data shall be retrieved by SIA
(Smart Phone Interface Application) or PIA (PC Interface Application) modules
based on necessity for transmitting to USP or PC.
The UWBT is classified into four types based on the type of sensor interfaced
to it. The sensor inputs are handled by the DAL (Data Acquisition & Logging)
application. Possible sensor interfaces for which the device is design are
• Thermocouple
• RTD
• pH
• RH
The available Sensor Sampling Rate ranges from 10 samples/sec max to 1
sample/minute min.
11.1.1. EEPROM Memory Allocation and Record Format
The UWBT Device utilizes 128KB of serial EEPROM for recording the sensor
specific data and device configuration parameters. The EEPROM data will be
grouped as blocks of records for storing long hours of data. A record block (256
bytes) format at 128K EEPROM is represented in the table below.
Table 11-1: Allotment of Location for Each Record Block
• Each record block as size of 256 bytes, contains the headers for Date & Time
stamp, Number of Records, Record interval, Block Stamp and Record Size for
reconstructing the records at later stage
• The calculated CRC is placed in the last two bytes
0x00 0x01 0x02 0x03 0x04 0x05 0x06 0x07
0x00
Number of
Records
Record
Interval
Day Month Year Hour Min Sec
0x01
Block Stamp
High
Block Stamp
Low
Record Size R R R R R
0x02 R R R R R R R R
0x03 R R R R R R R R
0x04 R R R R R R R R
… R R R R R R R R
0x1F R R R R R R CRC CRC