Specifications

CHAPTER 4
OPERATION
4-5
DT-203X, DT-105X and DT-110X display series
4.4.1. TDL protocol.
The TDL protocol must be selected to save new messages into the memory.
After power on, the display always shows all messages stored in the memory in
Continuous mode. The Continuous mode is reset when the serial line sends a message to
display. In Message mode, the display only shows the last message received. To return to
continuous mode, see 4.4.1.8.4 “Set CONTINUOUS mode”.
Every time the display receives a message with its address, the display returns a
response message. This rule is not valid when the message received has address 0 and the
address display is > 0. Messages with address 0 are used to send the same message to all
displays in a network.
If display address and message address are both 0, the display returns a
response message.
The block structure is:
00h 02h
Address
Bytes
Data
00h 0Dh
CRC
00h 03h
00h 02h: Start block. Always 00h 02h.
Address: Display address. Address range 00h to FFh.
Bytes : Number of bytes.
Data: Message send to display.
00h 0Dh: End of data.
CRC : Crc value.
00h 03h: End block. Always 00h 03h
4.4.1.1. Start block.
2 bytes.
Always “00h 02h”.
4.4.1.2. Address.
1 byte.
The address display in the network. Valid range between 00h and FFh.
The display and the message address allows transmissions to be controlled on the
network between one master and up to 255 slaves. The display always acts a slave. The
display only responses if it has its own address. The display only shows the message if it has its
own address or it has the address 0.
Message Address
Display Address
Display Response
Display Message
0
0
YES
New message
2
0
NO
No change
0
1
NO
New message
3
4
NO
No change
3
3
YES
New message