Rockwell Automation 1794-IE4XOE2,1794-IE8,1794-OE4,D17946.5.2 FLEX I/O ANALOG MODULE User Manual

Page 48

Advertising
background image

5–4

How Communication Takes Place and I/O Image Table Mapping with the DeviceNet Adapter

Publication 1794Ć6.5.2 - May 1996

Size

00

01

02

03

04

05

06

07

08

09

10

11

12

13

14

15

Decimal Bit

Read Words

00

01

02

03

04

05

06

07

10

11

12

13

14

15

16

17

Octal Bit

S

Analog Value Channel 7

Read Word 8

PU

Not used - set to zero

U7

U6

U5

U4

U3

U2

U1

U0

Read Word 9

Where:

PU = Power up bit - included in series B modules only.

U = Underrange bits for 4Ć20mA inputs

S = sign bit (in 2's complement)

Analog Input Module (1794-IE8/B) Write

Decimal Bit

15

14

13

12

11

10

09

08

07

06

05

04

03

02

01

00

Size

Octal Bit

17

16

15

14

13

12

11

10

07

06

05

04

03

02

01

00

Write Words

C7

C6

C5

C4

C3

C2

C1

C0

F7

F6

F5

F4

F3

F2

F1

F0

Write Word 1

Not used - set to 0

Write Word 2 thru 6

Where:

C = Configure select bit

F = Full range bit

Range Selection Bits for the 1794-IE8/B Analog Input Module

Channel No.

Channel 0

Channel 1

Channel 2

Channel 3

Channel 4

Channel 5

Channel 6

Channel 7

F0

C0

F1

C1

F2

C2

F3

C3

F4

C4

F5

C5

F6

C6

F7

C7

Decimal Bit

00

08

01

09

02

10

03

11

04

12

05

13

06

14

07

15

0-10V dc/0-20mA

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

4-20mA

0

1

0

1

0

1

0

1

0

1

0

1

0

1

0

1

Ć10 to +10V dc

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

Off

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

C = Configure select bit

F = Full range bit

1

When configured to off, individual channels will return 0000H on Series B modules, and 4Ć20mA on Series A modules.

Word/Bit Descriptions for the 1794-IE8/B Analog Input Module

Word

Decimal Bit

Definition

Read Word 1

Bits 00-14

Channel 0 analog data - 12Ćbit left justified two's complement

number; unused lower bits are zero; 4Ć20mA uses all 16 bits.

Read Word 1

Bits 15

Channel 0 analog data sign bit.

Read Word 2

Bits 00-14

Channel 1 analog data - 12Ćbit left justified two's complement

number; unused lower bits are zero; 4Ć20mA uses all 16 bits.

Read Word 2

Bits 15

Channel 1 analog data sign bit.

Read Word 3

Bits 00-14

Channel 2 analog data - 12Ćbit left justified two's complement

number; unused lower bits are zero; 4Ć20mA uses all 16 bits.

Read Word 3

Bits 15

Channel 2 analog data sign bit.

Read Word 4

Bits 00-14

Channel 3 analog data - 12Ćbit left justified two's complement

number; unused lower bits are zero; 4Ć20mA uses all 16 bits.

Read Word 4

Bits 15

Channel 3 analog data sign bit.

Advertising