Specifications

CR3000 Overview
When running in sequential mode, the datalogger uses a queuing system for
processing tasks similar to the one used in the pipeline mode. The main
difference when running a program in sequential mode is that there is no
prescheduled timing of measurements; instead, all of the instructions are run in
the order they occur in the program. A priority scheme is used to avoid
conflicting use of measurement hardware. In this scheme the main scan has
the highest priority and prevents other sequences from using measurement
hardware until the main scan is completed (including processing). Other tasks,
such as processing from other sequences and communications, can occur while
the main sequence is running. Once the main scan has finished other
sequences have access to measurement hardware with the order of priority
being the background calibration sequence followed by the slow sequences in
the order they are declared in the program. Note that Measurement tasks have
priority over other tasks such as processing and communication to allow
accurate timing needed within most measurement instructions, e.g.
integrations.
OV2.4 Data Tables
The CR3000 can store individual measurements or it may use its extensive
processing capabilities to calculate averages, maxima, minima, histograms,
FFTs, etc., on periodic or conditional intervals. Data are stored in tables such
as listed in Table OV2-1. The values to output are selected when running
ShortCut or when writing a datalogger program directly.
Table OV2-1. Typical Data Table
TOA5 Fritz CR3000 1079 CR3000.Std.1.0 CPU:TCTemp.CR1 51399 Temp
TIMESTAMP RECORD RefT_Avg TC_Avg(1) TC_Avg(2) TC_Avg(3) TC_Avg(4) TC_Avg(5) TC_Avg(6)
TS RN degC DegC DegC DegC DegC DegC DegC
Avg Avg Avg Avg Avg Avg Avg
10/28/2004 12:10 119 23.52 23.49 23.49 23.5 23.49 23.5 23.5
10/28/2004 12:20 120 23.55 23.51 23.51 23.51 23.51 23.51 23.52
10/28/2004 12:30 121 23.58 23.52 23.53 23.53 23.53 23.53 23.53
10/28/2004 12:40 122 23.58 23.53 23.54 23.54 23.54 23.54 23.54
OV2.5 PakBus
®
Communication with the CR3000
The CR3000 uses the PakBus network communications protocol. PakBus
increases the number of communications and networking options available to
the datalogger. In addition to communicating via its RS-232 and/or CS I/O
ports, the CR3000 can also communicate via the digital I/O COM ports.
Some of the advantages of PakBus are:
• Routing – the CR3000 can act as a router, passing on messages intended
for another logger. PakBus supports automatic route detection and
selection.
• Short distance networks with no extra hardware – A CR3000 can talk to
another CR3000 or CR1000 over distances up to 30 feet by connecting 3
wires between the dataloggers: transmit, receive, and ground. A PC
communicating with one of these loggers (e.g. via a phone modem or RF
OV-10