Function Description

The SIG_WRITE function allows writing a specific signature to a memory card BMX RM •••. An application embedding the SIG_CHECK EF only runs on a memory card that contains an expected signature.

SIG_WRITE writes a signature to the memory card inserted in a BMX P34 •••• CPU. The signature consists of 8 words (16 bytes).

This EF can take several tenths of milliseconds to perform a physical write to the memory card, therefore, make sure that the application can support the extra time.

NOTE: %S62 is set to 1 when a card contains a signature, no matter what the value of the 8 words written.
NOTE: This EF can only be used on a BMX P34 ••••, Version 2.2 or higher.

FBD Representation

The representation in FBD of the SIG_WRITE function (with example data) is as follows:

Ladder Representation

The representation in Ladder of the SIG_WRITE function (with example data) is as follows:

IL Representation

The representation in IL of the SIG_WRITE function (with example data) is as follows:

SIG_WRITE (

SIG0 := 16#45de,

SIG1 := 16#78aa,

SIG2 := 16#2cde,

SIG3 := 16#ac3f,

SIG4 := 16#5c81,

SIG5 := 16#2702,

SIG6 := 16#b312,

SIG7 := 16#2ed4,

)

ST sigStat

ST Representation

The representation in ST of the SIG_WRITE function is as follows: STATUS:=SIG_WRITE(SIG0, SIG1, SIG2, SIG3, SIG4, SIG5, SIG6, SIG7);

Parameter Description

The following table describes the SIG_WRITE Input parameters:

Parameter

Type

Comment

SIG0..SIG7

WORD

8 Words containing the signature to write into the memory card

The following table describes the SIG_WRITE Output parameters:

Parameter

Type

Comment

STATUS

WORD

Result of writing operation:

  1. No detected error

  2. Detected error, such as no memory card or the card is write protected