VK204-25-422 Matrix Orbital, VK204-25-422 Datasheet - Page 22

• Manufacturer Part Number: VK204-25-422
• Description: VF CHARACTER DISPLAY 20X4 RS422
• Manufacturer: Matrix Orbital
• Series: VK204-25r

Specifications of VK204-25-422

• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Commands
1. Communications
1.1. Changing the I2C
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
1.2. Changing the
Immediately changes the baud rate. Not available in I2C. Baud rate can be temporarily forced to 19200 by a
manual override.
Speed
1.3. Setting a Non-Standard
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
1.4. Transmission
Selects the protocol used for data transmission from the display. Data transmission to the display is not affected.
Must be set to the protocol in use to receive data correctly.
Protocol
Slave Address
Baud Rate
Baud Rate
Protocol Select
1 byte, valid settings shown below
2 bytes, calculations shown below, standard crystal speed is 16MHz
1 byte, even value
1 byte, 1 for Serial (RS232/RS422/TTL/USB) or 0 for I2C
Speed
Rate
Dec
Hex
ASCII
Equation 1: Speed Byte Calculation
Dec
Hex
ASCII
Dec
Hex
1200
83
254 57
FE 39
Dec
Hex
254 160
2400
■ 9
254 51
FE A0
41
FE 33
■ 3
Speed
Speed
Speed
254 164
Equation 3: Baud Rate Error Calculation
4800
Table 17: Accepted Baud Rate Values
207
FE A4
Protocol
Protocol
Address
Address
Address
9600
103
Speed
Speed
19200
51
Equation 2: Actual Baud Rate Calculation
28800
34
38400
25
57600
16
115200
8
22