2.4The CD Function Block

In case a GSM modem or an analog modem that supports Calling Line Identification Presentation (CLIP) is called, the number of the calling partner is sent by the modem by the AT notification "+CLIP" attached to the RING notification. α2 extracts the callers's number after a given number of RING notifications.

In case the numbers of digits of both phone numbers and the phone numbers itself are equal, the CD FB output is switched on.

To enter or edit the SMR parameters, double click on the icon to open the Short Message Receiving dialog box described in Section 2.4.1.

A)

(C

B)

A) The Input Signal

Enables the CD FB operation.For normal operation the Input must be ON.

When Input is OFF, the output is hold and the function block doesn't check caller's number. Input is ON when left open (not connected).When Reset and Input are ON at the same time, only Reset becomes active.

B) The Reset Signal

Resets the bit output when ON

Reset takes priority over Input and takes priority over an incoming call.Thus, when Reset is ON, an incoming call has no affect.

Reset is OFF when not connected.

C) The Output Signal

Bit output.

The output is set ON, when the caller's number is equal to the stored phone number and Input is ON.The output state is hold, when Input is OFF, and it is reset (set OFF), when Reset is ON.

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2.4.1Call Detect (CD)

The Call Detect dialog box is used for a Phone Number and Number of rings setup..

A)

B)

C)

D)

E)

F)

(G

A) Comment

This edit box is used to enter a comment that will be displayed above the CD icon and only when the "Display Comment" box is checked.

B) Display Signal Number

If this check box is checked the signal number will be displayed next to the function icon.

C) Display Monitor Information

If this check box is checked the monitor information will be displayed below the function icon. This information is displayed only in monitor and simulation mode.

D) Phone Number

Length: 28 characters, including " +,-,(,),*,0,1,2,3,4,5,6,7,8,9 "

Asterix Character in phone number

The asterix character '*' can be used to terminate phone number or can be stand-alone.

It takes place for any combination of numbers. Using the '*', one CD FB can switch for a group of phone numbers.

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Table 2.5: Phone numbers and Outputs

E) Maintenance

If this check box is checked maintenance mode will be selected.

F) Retentive

Check the "Retentive" checkbox is store the output value even after a Power cut.

G) Number of RING before call detect

Range: 1~20

Cautions for the use of both Call Detec and remote access

- When it remotely accesses from the same telephone number for Call Detect, CD and FB operate.

Cautions for misoperations

- CD FB operates also by a misoperation of a telephone.

In order to avoid serious injury and the machine damage caused by unintended CD FB operation, provide safety devices as countermeasure.

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