B&B Electronics Command Response Protocol HVD100A3 User Manual

Page 9

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HDV100A3 Command & Response Manual-1306cr

5

B&B Electronics -- 707 Dayton Rd. -- PO Box 1040 -- Ottawa, IL 61350

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

RS-232 Baud Rate Setup

To set the baud rate for the RS-232 port, set a general command code of 08.
Set the function code to 01. Then set 3 control bytes as follows.

Function Start

of
Frame

Control
Bytes

Command
Code

Function
Code

UB3 Baud

1

Baud
2

Data
Bytes

Check
Sum

Byte #

1

2

3

4

5

6

8

9

10

Value

01

05 08

01 00



Setting UB3

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

Divisor
Latch

Set
Break

Set
Parity

Even
Parity

Parity
Enable

Stop
Bits

Word
Length 1

Word
Length 0


Bit 7 = 1 allows baud rate divisor to be changed. 0 baud rate change is
blocked. Bit 7 should not be set. The setting and resetting of this bit is
handled internally.

Bit 6 = 1 forces the transmitter output to a logic 0 for alerting the remote
receiver to a line break. 0 indicates no break condition.

Bit 5, 4 and 3 work together to set parity

Bit 5

Bit 4

Bit 3

Parity Selection

*

*

0

No parity (default)

0

0

1

Odd parity

0

1

1

Even parity

1

0

1

Force parity “1”

1

1

1

Force parity “0”

*Don’t

care

state.


Bit 2, stop bit, works in conjunction with bits 1 and bit 0

Bit 2

Word Length (bits)

Stop Bit Length

0

5,6,7,8

1 (default)

1

5

1

6,7,8

2

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