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Commands, Communications, 5 commands – Matrix Orbital GLK24064-16-1U User Manual

Page 20: 1 communications

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5 Commands

5.1 Communications

1.1 Changing the I2C
Slave Address

Dec
Hex
ASCII

254 51

FE 33

3

Address
Address
Address

Immediately changes the I2C write address. Only even values are permitted as the next odd address will become
the read address. Default is 80.

Address

1 byte, even value


1.2 Changing the
Baud Rate

Dec
Hex
ASCII

254 57

FE 39

9

Speed
Speed
Speed

Immediately changes the baud rate. Not available in I2C. Baud rate can be temporarily forced to 19200 by a
manual override.

Speed

1 byte, valid settings shown below

Table 15: Accepted Baud Rate Values

Rate

9600 14400 19200 28800 38400 57600 76800 115200

Speed

207

138

103

68

51

34

25

16


1.3 Setting a Non-Standard
Baud Rate

Dec
Hex

254 164

FE A4

Speed
Speed

Immediately changes the baud rate to a non-standard value. Speed must be a whole number between 977 and
153800. Due to rounding, error increases with baud rate, actual baud must be within 3% of desired baud to ensure
accurate communication. Not available in I2C. Can be temporarily forced to 19200 by a manual override.

Speed

2 byte, calculations shown below

Equation 1: Speed Byte Calculation

Equation 2: Actual Baud Rate Calculation

Equation 3: Baud Rate Error Calculation

1.4 Transmission
Protocol Select

Dec
Hex

254 160

FE A0

Protocol
Protocol

Selects the protocol used for data transmission to the host. Data transmission from the host is not affected. Must
be set to the protocol in use to receive data correctly.

Protocol

1 byte, 1 for Serial (RS232/RS422/TTL/USB) or 0 for I2C