15.2
Command (CMD)
The following commands are defined for the interface board:
CMD
Description
MAN
Manufacturer ID
BZZ
Buzzer Control Command
FAN
Fan Control Command
ETC
Elapsed Time Counter
TMP
Temperature Sensor
LIS
Light Sensor
15.2.1
Data Length (LEN)
This byte contains the length of the DATA field. The minimum value is 0 bytes. No messages have been defined with a
length of more than 35 bytes.
15.2.2
Inverse Header Checksum (IHCHK)
This is a simple 8 bit checksum. The checksum byte is initialized to 0. A bit-wise inversion of bytes 0 to 5 is performed.
The 8 bit sum (without carry) of inverted bytes 0 to 5 and byte 6 shall be 0xFF.
If a message fails the checksum, the interface board will reply with a NACK message with zero data. This requirement
does not apply to broadcasted messages.
15.2.3
Data Sent (DS)
The DS field is only transmitted as a mirror of the sent data.
15.2.4
Data Field (DATA)
The data field is only transmitted if LEN is greater than 0. The field carries additional data depending of the message
command.
15.2.5
Inverse Data Checksum (IDCHK)
The inverse data checksum is only transmitted if LEN is greater than zero. The checksum is initialized to 0. A bit-wise
inversion of DATA field(s) is performed. The 8 bit sum (without carry) of the inverted bytes and the IDCHK shall be
0xFF.
The interface board will reply with a NACK to all messages with invalid checksums. This requirement does not apply
to broadcasted messages.
15.2.6
No Operation (NOP)
This is empty data ‘0x00’ and only used as a filler between detection bytes for the reset command.
User Reference Manual – DuraPanel series
PN: 07353-000 Rev B Page 19
