B&B Electronics 485SDD16 manual MSdefs = MSdefs and mask LSdefs = LSdefs and mask

Models: 485SDD16

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Step 3 - Receiving the data:

MSdefs$ = INPUT$(1,#1)

LSdefs$ = INPUT$(1,#1)

MSpups$ = INPUT$(1,#1)

LSpups$ = INPUT$(1,#1)

Maddr$ = INPUT$(1,#1)

Mtdly$ = INPUT$(1,#1)

Step 4 - Manipulating the data:

MSdefs = ASC(MSdefs$)

LSdefs = ASC(LSdefs$)

MSpups = ASC(MSpups$)

LSpups = ASC(LSpups$)

Maddr = ASC(Maddr$)

Mtdly = ASC(Mtdly$)

Step 5 - Determining the I/O line definitions:

MSdefs = MSdefs AND mask

LSdefs = LSdefs AND mask

By "ANDing" the value of MSdefs or LSdefs with the appropriate mask of an I/O line, the I/O line definition can be determined. If the status is equal to zero the I/O line is an INPUT. If the status is not equal to zero the I/O line is an OUTPUT. Table 5.1 shows the mask values for each I/O line.

Step 6 - Repeat Step 5 until the status of each I/O line has been determined.

Step 7 - Determining an OUTPUT's Power-up state:

MSpups = MSpups AND mask

LSpups = LSpups AND mask

By "ANDing" the value of MSpups or LSpups with the appropriate mask of an Output line, the Output line definition can be determined. If the status is equal to zero the Output power-up state will be LOW. If the status is not equal to zero the Output power-up state will be HIGH. Table 5.1 shows the mask values for each I/O line.

Step 8 - Repeat Step 7 until the power-up state of each Output line has been determined.

Example 5.2 - Determining the definition and power-up state of I/O lines #2 & #10 of module #5.

485SDD16-1005 Manual

23

B&B Electronics --

707 Dayton Road -- Ottawa, IL 61350

PH (815) 433-5100 -- FAX (815) 433-5104

Maddr = 5 mask = &H4

Cmnd$ = "!" + CHR$(Maddr) + "RC" PRINT #1, Cmnd$;

MSdefs$ = INPUT$(1,#1)

LSdefs$ = INPUT$(1,#1)

MSpups$ = INPUT$(1,#1)

LSpups$ = INPUT$(1,#1)

Maddr$ = INPUT$(1,#1)

Mtdly$ = INPUT$(1,#1) MSdefs = ASC(MSdefs$) LSdefs = ASC(LSdefs$) MSpups = ASC(MSpups$) LSpups = ASC(LSpups$) Maddr = ASC(Maddr$) Mtdly = ASC(Mtdly$) MSdefs = MSdefs AND mask LSdefs = LSdefs AND mask MSpups = MSpups AND mask LSpups = LSpups AND mask

If LSdefs equals zero then I/O line #2 is an INPUT and if not equal to zero then I/O line #2 is an OUTPUT. If MSdefs equals zero then I/O line #10 is an INPUT and if not equal to zero then I/O line #10 is an OUTPUT. If LSpups equals zero then Output line #2's power-up state is LOW and if not equal to zero then Output line #2's power-up state is HIGH. If MSpups equals zero then Output line #10's power- up state is LOW and if not equal to zero then Output line #10's power-up state is HIGH. Maddr is the decimal address of the module. Mtdly is the decimal number of character times that make up the turn-around delay.

Set Output States Command

The Set Output States command is used to set the states of any I/O line that is defined as an output. This command requires two data bytes. Refer to this command in Chapter 3 for more information.

Step 1a - Construct the command string:

Set appropriate outputs HIGH

MSstates = MSstates OR mask

LSstates = LSstates OR mask

By "ORing" the current states with the appropriate mask of a digital output line, the output's bit will be set to a "1" (HIGH).

24485SDD16-1005 Manual

B&B Electronics -- 707 Dayton Road -- Ottawa, IL 61350

PH (815) 433-5100 -- FAX (815) 433-5104

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B&B Electronics 485SDD16 manual MSdefs = MSdefs and mask LSdefs = LSdefs and mask, Set Output States Command