15 DIGITAL INTERFACE

The OSP portable IR thermometer can be equipped with a digital interface.

The interface circuit is essentially based on the serial communication interface subsystem (SCI) on the chip of the microcontroller. The output voltage levels are TTL at 0 to +5 V.

An optional adapter to convert the voltage level from 0 to +5 V to RS232 standard levels can be supplied. This adapter is required to interface OSP with a Personal Computer.

15.1Digital output wiring practice

The wiring to digital output signals is made through a mini DIN connector mounted on the lower end of the case. The pertinent connections are indicated below :

Rx IRtec P

Tx IRtec P

Dig. ground

Analog Output

Anal. ground

5 V

Female miniDIN connector

(case mounted - external view)

For easy interconnections a miniDIN connector with cable (cat. EE420123) can be supplied on request. The color codes of the conductors can change with different suppliers; please check before using.

6 5 4

8

73

1 2

Front view

 

LINDY

CINCH

pin 1 :

brown

black

pin 2 :

red

green

pin 3 :

green

blue

pin 4 :

gray

gray

pin 5 :

purple

yellow

pin 6 :

blue

white

pin 7 :

orange

red

pin 8 :

yellow

brown

15.2TTL to RS 232 adapter

The cat. BB530001 TTL to RS232 adapter consists of a cable to which are connected a male mini DIN connector (for OSP) and a DB25 connector, that contains the electrical circuitry (for the PC).

The basic circuit and connections are as follows:

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Omega OSP SERIES manual Digital Interface, Digital output wiring practice, TTL to RS 232 adapter