Installation manual

Operation and Installation Manual
2013 Cervis, Inc.
41
Once the 24 characters are completed, the command for sent the cursor to line 1, column 1
must be written; otherwise, all previously written will be lost. We still have only used four
packages of 8-bytes; therefore, we have another 4-bytes available to send, for example, the
state of the LEDs and the Buzzer.
Switching On the LEDs and Buzzer
To establish the state of the LEDs and the Buzzer, we have to send a 2-data package. This
package must be preceded by the identifier COB_ID=0x200+node_ID.
LEDs  From 0 to 255 value
Buzzer  0 or 1 value
The first data package determines if the LEDs are lit green, red, or amber (green/red combined).
The value is a binary code that reads as follows:
Table 15. First Data Packet: LED State Values
LED 4
LED 3
LED 2
LED 1
Red Green Red Green Red Green Red Green
128 64 32 16 8 4 2 1

Data 0 0 1 1 1 0 0 1 = 57h
The second data packet determines if the buzzer is ON (1) or OFF (0).
Table 16. Second Data Packet: LEDs & Buzzer Determination
Position
Message (Hex)
Meaning
LCD 1
57 LED 1 = Green; LED 2 = Red; LED 3 = Amber; LED 4 = Off
LCD 2
01 Buzzer ON
LCD 3
LCD 4
LCD 5
LCD 6
LCD 7
LCD 8
Important: The last byte of the transmitted second packet could have different values:
• If the value is 1: The CAN message from the master is already sent to the transmitter and
the receiver could receive one more messge and save it to later send to the transmitter.
• If the value is 0: The transmitter has already received a CAN message and is ready to
receive another.
• If the value is 3: The buffer is full and is waiting for confirmation from the transmitter. A
message may be lost if sent while in this state because it has nowhere to be stored.