User`s manual

Maxiflex T2 CPU User Manual 15 -© Omniflex
UMM124XBR04.pdf
3. T2 CPU’s and the MAXIFLEX Architecture
3.1 System Architecture
A diagram of the MAXIFLEX System Architecture is shown in Figure 3.1
This diagram shows the T2 CPU in a system with a Programmable Network Interface
Module (NIM) and a conventional I/O Module (IOM). NIM’s and IOM’s can be arranged in
any order in the available I/O Module slots of the system.
3.2 CPU Functions
The T2 CPU contains the following functions:
3.2.1 Real-Time Clock
These CPU’s have a real-time clock as a standard function. This clock has the
following features:
♦ Battery-backed to retain real time while power is off.
♦ Resolution to 10 milliseconds
♦ Current Time available in the Data Interchange Table
♦ Last Power up Time available in the Data Interchange Table
♦ Last Power Down Time available in the Data Interchange Table
3.2.2 I/O Scanning
This function is responsible for the scanning of conventional I/O modules installed on
Maxiflex base, sorting the data into convenient tables according to type of I/O
(Analogue or Digital; Input or Output) and reading/writing this data to/from the CPU’s
Data Interchange Table (DIT) for easy access from any of the network ports.
3.2.3 I/O Module Management
This function is responsible for continuously monitoring all slots of the Maxiflex I/O
base, keeping track of the currently installed module types. This function also
maintains a copy of the intelligent I/O module configuration data in the CPU, allowing
I/O modules to be changed without the need to reconfigure them.
3.2.4 FORTH User Program
While not necessary in the majority of applications, due to the rich set of other
features in this CPU, the FORTH programming language can be used to customise
any part of the system to suit the application, from simple data scaling, to complex
custom serial port protocols. The Forth program has access to the following features
in the CPU:
♦ Direct access to all Data Interchange Tables in the system
♦ Direct access to the serial port for custom protocols
♦ 8 independent timers with a resolution of 10 milliseconds
♦ Remotely programmable