DekTec DTM-3200 IP-ASI Converter - Manual (Page 41)

DTM-3200 – OEM Ethernet TSoIP Converter
User Manual
41
Appendix D. Communication Example
In the examples below, grey areas in the timing diagrams are sent by the DTM-3200, while white
areas are sent by the master. The address of the DTM-3200 in these examples is 0x12.
Write command on RS-XXX serial interface
Figure 9 shows the write command of the FEC-enable at the receive channel settings (category
0x81, setting 4, index 0). All values are displayed as ASCII characters.
Figure 9: Write FEC enable in the receive channel settings
The command consists of the following parts:
 Start character ‘STX’
 Two hexadecimal address characters (“12”)
 Two hexadecimal category characters (“81”)
 Two hexadecimal setting characters (“04”)
 A write character ‘W’
 Four hexadecimal index characters (“0000”)
 Two hexadecimal characters (“01”)
 Two hexadecimal checksum characters (“58”, See Table 1)
 Stop character ‘ETX’
Table 1: Checksum computation
Characters ASCII value
STX 0x02
1 0x31
2 0x32
8 0x38
1 0x31
0 0x30
4 0x34
W 0x57
0 0x30
0 0x30
0 0x30
0 0x30
0 0x30
1 0x31
5 0x35
8 0x38
ETX 0x03
Sum: 0x2A8
Checksum: 0x58