Apex Digital 5708009-C manual Ae Bus Protocol

Models: 5708009-C

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AE BUS PROTOCOL

Advanced Energy®

The host computer must finish one transaction with the Apex generator before it initiates another one, either with the same unit or any other unit.

Note: The Apex generator sends data through pin 2 (TXD.D). This pin must be connected to the receive pin (RXD.D) on the host computer’s PC serial connector. The receive pin is normally pin 2 for a standard, 9-pin PC serial port and normally pin 3 for a standard, 25-pin PC serial port.

AE BUS PROTOCOL

The AE Bus protocol uses pure binary data (nothing is coded in ASCII) and is designed to facilitate direct communications between a host computer and the Apex generator.

The AE Bus message packet combines chunks of information in such a way that groups of information can be sent over communications lines at one time. Five types of information (fields) make up communications message packets (see Figure 4-5.):

Header (address and the length of Data field)

Command (see the AE Bus command list later in this chapter)

Optional length byte

Data

Checksum (aids in error checking)

Figure 4-5. shows the organization of these data fields in the AE Bus message packet. The subsequent paragraphs describe each data field in detail.

Command

Data (0-255 bytes)

0-FFh

 

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0

7

6

5

4

3

1

0

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0

7

6

5

4

3

2

1

0

Header

Optional

Checksum

5-bit address

 

 

3-bit length

 

 

1138

Figure 4-5.Graphic representation of a RS-232, AE Bus message packet

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5708009-C

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Apex Digital 5708009-C manual Ae Bus Protocol, 5. Graphic representation of a RS-232, AE Bus message packet