Matrix Orbital LK202-25 Legacy - Manual (Page 37)

7.4.2 Search command (254 200 2)
This is used to find the addresses of all 1-Wire devices on the bus. After this command the display will
return one or more “Display return protocol” packets containing either an error code or addresses of 1-wire
packets.
Table 19: Search Return Packet
Offset
(Bytes)
Offset
(Bytes)
Description
0 2 0x232A - Preamble
2 1 0x8A - Packet is 10 bytes long, an-
other address will follow 0x0A -
Packet is 10 bytes long, this is the
last address
3 1 0x31 - 1-Wire Packet Type
4 1 Error Code (0x00 for success)
5 8 1-Wire Address
13 1 CRC8 - 0x00 means the last address
was valid
8 Appendix: Command Summary
8.1 General
The operation of the display is controlled by a simple and consistent command set. Commands control;
• Text display
• Graphics display
• Keypad interface
• Miscellaneous operating parameters
This chapter includes summary tables of all commands.
8.2 Issuing Commands
Commands are issued to the display by the controller. In a test setup, commands can be issued to
the display by means of a BASIC program, using the chr$( ) function. In the tables below, we’ve shown
commands in hex, ASCII and decimal form. All commands begin with the prefix character 0xFE (254
decimal). These commands are issued on the serial communications link (I 2 C or RS-232) at the currently
defined baud rate.
For example (using BASIC in a test setup), the user could issue the command to clear the screen on the
display by including the line:
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