SMAR TP302, Owner'S Operation And Maintenance Manual, Page: 19 / 54

Section 2
2.1
OPERATION
Functional Description – Hall Sensor
Sensor hall supplies an output voltage proportional to the applied magnetic field. This magnetic
sensor is ideal for use in system of sensor of linear or rotary position. The mechanical vibrations do
not affect sensor hall.
Functional Description – Electronics
Refer to the block diagram. The function of each block is described below.
Figure 2.1 - TP302 Block Diagram
Central Processing Unit (CPU), RAM, FLASH and EEPROM
The CPU is the intelligent portion of the transmitter, being responsible for the management and
operation of measurement, block execution, self-diagnostics and communication. The program is
stored in a FLASH memory for easy upgrade and saving data on power-down event occurrence. For
temporary storage of data there is a RAM. The data in the RAM is lost if the power is switched off,
however the main board has a nonvolatile EEPROM memory where the static data configured that
must be retained is stored. Examples of such data are the following: calibration, links and
identification data.
Controller Communication
Monitors line activity, modulate and demodulate communication signals; inserts and deletes start
and end delimiters, and check integrity of frame received.
Power Supply
Takes power of the loop-line to power the transmitter circuit.
Power Isolation
Isolates the signals to and from the input section, the power to the input section must be isolated.
A/D
The A/D converts the input signals to a digital format for the CPU.