====== Alarm memory ======

{{:en:mervis-ide:35-help:bd50.png}}

===== Block name =====

BD50_ALARM_MEMORY

===== ST call =====

<code st-iec>
PROGRAM TEST_BD50
  VAR
 BOOL1, BOOL2, BOOL3, BOOL4, BOOL5, BOOL6:BOOL;   
   FB : LIB.CORE.V1_0.BD50_ALARM_MEMORY;
   END_VAR
  FB.IN[1] := BOOL3;
  FB.IN[2] := BOOL4;  
    FB(ACK:=BOOL1,RESET:=BOOL2);
    BOOL5 := FB.OUT[1];
     BOOL6 := FB.OUT[2];
END_PROGRAM
</code>

===== Library =====

LIB\CORE

===== Version =====

V1.0

===== Description =====

The block is an alarm memory, with up to 16 alarms.

===== Inputs =====

|Input          |Type                           |Description                                                                                                             |Default value    |
|IN             |[[en:mervis-ide:35-help:035-software_basic:060-libraries:015-proto|MULTIIOBOOL]]|Inputs of the alarm signals as an array                                                                                 |[False,...,False]|
|ACK            |BOOL                           |Acknowledge. If //IN=TRUE// and rising edge comes to //ACK// then //ACKNOWLEDGED=TRUE// (while keeping //MEMORY=TRUE) //|False            |
|RESET          |BOOL                           |Reset of the alarm memory and ACKNOWLEDGED output.                                                                      |False            |
|IN0,IN1,..,IN15|BOOL                           |Inputs of the alarm signals                                                                                             |                 |

===== Outputs =====

|Output            |Type                           |Description                                                                                                                     |
|OUT               |[[en:mervis-ide:35-help:035-software_basic:060-libraries:015-proto|MULTIIOBOOL]]|Alarm output signals as an array.                                                                                               |
|ACKNOWLEDGED      |[[en:mervis-ide:35-help:035-software_basic:060-libraries:015-proto|MULTIIOBOOL]]|Indication that an alarm has been acked                                                                                         |
|MEMORY            |BOOL                           |Alarm memory                                                                                                                    |
|ALRSTATUS         |INT                            |Status of the alarm block (bit 8 indicates //IN=TRUE//, bit 9 indicates //ACKNOWLEDGED=TRUE//, bit 10 indicates //MEMORY=TRUE//)|
|OUT0,OUT1,..,OUT15|BOOL                           |Alarm output signals. OUT is in TRUE until an alarm has been reset.                                                             |

===== Function =====

This block is dedicated to deal with alarm states. The alarm signal is at the //IN// input. A rising edge on the //IN// input sets //MEMORY// to //TRUE// (alarm memory). The alarm can be reset by a rising edge at the //RESET// input. If //IN=FALSE// at the reset time, then //MEMORY// goes to FALSE. If the alarm is active (//IN=TRUE//), it can not be reset by the //RESET// input, but may be acknowledged by a rising edge brought to the //ACK// input. Note that in ST, the indeces are 1...16 rather than 0...15.\\


//alrstatus values//:

  * //alrstatus//=256 - at least one alarm is active.
  * //alrstatus//=512 - at least one alarm has been acknowledged
  * //alrstatus//=1024 - //memory// = true, alarm was active but has not been reset.\\


The //alrstatus// value may be addition of more of these states.\\


===== Application example =====

{{:en:mervis-ide:35-help:bd50_example.png}}