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2 changing the i, C slave address, 3 changing the baud rate – Matrix Orbital VK204-25 Legacy User Manual

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4.1.4

USB Communication

The VK204-25-USB is a USB device that offers identical communication protocol as the serial comport.

capable of communicating via a USB interface. The USB communications are identical to the serial commu-
nications. Communication is via a virtual com port, which is created in the operating system by the drivers
necessary to install the USB display. The VK204-25-USB communicating via USB is capable of baud rates
of 19,200 bps to 115,200 bps. Other baud rates are subject to the limitation of the virtual com port driver. For
further information regarding supported operating systems, and driver limitations please contact technical
support.

4.2

Changing the I

2

C Slave Address

Syntax

Hexadecimal

0xFE 0x33 [adr]

Decimal

254 51 [adr]

ASCII

254 “3” [adr]

Parameters

Parameter

Length

Description

adr

1

The new I

2

C write address (0x00 -

0xFF).

Description

This command sets the I

2

C write address of the module between 0x00

and 0xFF. The I

2

C write address must be an even number and the read

address is automatically set to one higher. For example if the I

2

C write

address is set to 0x50, then the read address is 0x51.

NOTE

The change in address is immediate.

Remembered

Always

Default

0x50

4.3

Changing the Baud Rate

Syntax

Hexadecimal

0xFE 0x39 [speed]

Decimal

254 57 [speed]

ASCII

254 “9” [speed]

Parameters

Parameter

Length

Description

speed

1

Hex value corresponding to a baud
rate.

Matrix Orbital

VK204-25-USB

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