Hallo und erst mal danke für die schnellen Antworten.
Es handelt sich um einen Hoval Öl-Brennwertkessel der über eine Hoval Modbus-TCP-Erweiterung mit dem Netzwerk verbunden ist.
Hier mal ein Debug:
TXT: 16.04.2020, 16:06:06 | WAITING | <EOT><ACK><GS><NUL><SOH>
HEX: 16.04.2020, 16:06:06 | WAITING | 04 06 1D 00 01
TXT: 16.04.2020, 16:06:06 | TRANSMIT | <EOT><ACK><GS><NUL><SOH>
HEX: 16.04.2020, 16:06:06 | TRANSMIT | 04 06 1D 00 01
TXT: 16.04.2020, 16:06:07 | BUFFER IN | <NUL>h<NUL><NUL><NUL><ENQ><NUL><EOT><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:07 | BUFFER IN | 00 68 00 00 00 05 00 04 02 00 00
TXT: 16.04.2020, 16:06:07 | RESULT | <EOT><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:07 | RESULT | 04 02 00 00
TXT: 16.04.2020, 16:06:07 | WAITING | <ETX><ENQ>Ç<NUL><SOH>
HEX: 16.04.2020, 16:06:07 | WAITING | 03 05 C7 00 01
TXT: 16.04.2020, 16:06:07 | TRANSMIT | <ETX><ENQ>Ç<NUL><SOH>
HEX: 16.04.2020, 16:06:07 | TRANSMIT | 03 05 C7 00 01
TXT: 16.04.2020, 16:06:07 | BUFFER IN | <NUL>i<NUL><NUL><NUL><ENQ><NUL><ETX><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:07 | BUFFER IN | 00 69 00 00 00 05 00 03 02 00 00
TXT: 16.04.2020, 16:06:07 | RESULT | <ETX><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:07 | RESULT | 03 02 00 00
TXT: 16.04.2020, 16:06:07 | WAITING | <EOT><ENQ>ö<NUL><SOH>
HEX: 16.04.2020, 16:06:07 | WAITING | 04 05 F6 00 01
TXT: 16.04.2020, 16:06:07 | TRANSMIT | <EOT><ENQ>ö<NUL><SOH>
HEX: 16.04.2020, 16:06:07 | TRANSMIT | 04 05 F6 00 01
TXT: 16.04.2020, 16:06:07 | BUFFER IN | <NUL>j<NUL><NUL><NUL><ENQ><NUL><EOT><STX><NUL>õ
HEX: 16.04.2020, 16:06:07 | BUFFER IN | 00 6A 00 00 00 05 00 04 02 00 F5
TXT: 16.04.2020, 16:06:07 | RESULT | <EOT><STX><NUL>õ
HEX: 16.04.2020, 16:06:07 | RESULT | 04 02 00 F5
TXT: 16.04.2020, 16:06:07 | WAITING | <EOT><ACK>%<NUL><SOH>
HEX: 16.04.2020, 16:06:07 | WAITING | 04 06 25 00 01
TXT: 16.04.2020, 16:06:07 | TRANSMIT | <EOT><ACK>%<NUL><SOH>
HEX: 16.04.2020, 16:06:07 | TRANSMIT | 04 06 25 00 01
TXT: 16.04.2020, 16:06:07 | BUFFER IN | <NUL>k<NUL><NUL><NUL><ENQ><NUL><EOT><STX>ÿÿ
HEX: 16.04.2020, 16:06:07 | BUFFER IN | 00 6B 00 00 00 05 00 04 02 FF FF
TXT: 16.04.2020, 16:06:07 | RESULT | <EOT><STX>ÿÿ
HEX: 16.04.2020, 16:06:07 | RESULT | 04 02 FF FF
TXT: 16.04.2020, 16:06:07 | WAITING | <EOT><ACK><SUB><NUL><SOH>
HEX: 16.04.2020, 16:06:07 | WAITING | 04 06 1A 00 01
TXT: 16.04.2020, 16:06:07 | TRANSMIT | <EOT><ACK><SUB><NUL><SOH>
HEX: 16.04.2020, 16:06:07 | TRANSMIT | 04 06 1A 00 01
TXT: 16.04.2020, 16:06:07 | BUFFER IN | <NUL>l<NUL><NUL><NUL><ENQ><NUL><EOT><STX><SOH>J
HEX: 16.04.2020, 16:06:07 | BUFFER IN | 00 6C 00 00 00 05 00 04 02 01 4A
TXT: 16.04.2020, 16:06:07 | RESULT | <EOT><STX><SOH>J
HEX: 16.04.2020, 16:06:07 | RESULT | 04 02 01 4A
TXT: 16.04.2020, 16:06:08 | BUFFER IN | <NUL>ð<NUL><NUL><NUL><ENQ><DLE><EOT><STX><SYN>
HEX: 16.04.2020, 16:06:08 | BUFFER IN | 00 F0 00 00 00 05 10 04 02 16 8D
TXT: 16.04.2020, 16:06:09 | WAITING | <EOT><ENQ>õ<NUL><SOH>
HEX: 16.04.2020, 16:06:09 | WAITING | 04 05 F5 00 01
TXT: 16.04.2020, 16:06:09 | TRANSMIT | <EOT><ENQ>õ<NUL><SOH>
HEX: 16.04.2020, 16:06:09 | TRANSMIT | 04 05 F5 00 01
TXT: 16.04.2020, 16:06:10 | BUFFER IN | <NUL>m<NUL><NUL><NUL><ENQ><NUL><EOT><STX><SOH>Û
HEX: 16.04.2020, 16:06:10 | BUFFER IN | 00 6D 00 00 00 05 00 04 02 01 DB
TXT: 16.04.2020, 16:06:10 | RESULT | <EOT><STX><SOH>Û
HEX: 16.04.2020, 16:06:10 | RESULT | 04 02 01 DB
TXT: 16.04.2020, 16:06:10 | WAITING | <ETX><ENQ>Æ<NUL><SOH>
HEX: 16.04.2020, 16:06:10 | WAITING | 03 05 C6 00 01
TXT: 16.04.2020, 16:06:10 | TRANSMIT | <ETX><ENQ>Æ<NUL><SOH>
HEX: 16.04.2020, 16:06:10 | TRANSMIT | 03 05 C6 00 01
TXT: 16.04.2020, 16:06:10 | BUFFER IN | <NUL>n<NUL><NUL><NUL><ENQ><NUL><ETX><STX><NUL><BEL>
HEX: 16.04.2020, 16:06:10 | BUFFER IN | 00 6E 00 00 00 05 00 03 02 00 07
TXT: 16.04.2020, 16:06:10 | RESULT | <ETX><STX><NUL><BEL>
HEX: 16.04.2020, 16:06:10 | RESULT | 03 02 00 07
TXT: 16.04.2020, 16:06:11 | WAITING | <EOT>Cé<NUL><SOH>
HEX: 16.04.2020, 16:06:11 | WAITING | 04 43 E9 00 01
TXT: 16.04.2020, 16:06:11 | TRANSMIT | <EOT>Cé<NUL><SOH>
HEX: 16.04.2020, 16:06:11 | TRANSMIT | 04 43 E9 00 01
TXT: 16.04.2020, 16:06:11 | BUFFER IN | <NUL>o<NUL><NUL><NUL><ENQ><NUL><EOT><STX><SOH>6
HEX: 16.04.2020, 16:06:11 | BUFFER IN | 00 6F 00 00 00 05 00 04 02 01 36
TXT: 16.04.2020, 16:06:11 | RESULT | <EOT><STX><SOH>6
HEX: 16.04.2020, 16:06:11 | RESULT | 04 02 01 36
TXT: 16.04.2020, 16:06:12 | BUFFER IN | <NUL>ñ<NUL><NUL><NUL><ENQ><DLE><EOT><STX><NUL><DC3>
HEX: 16.04.2020, 16:06:12 | BUFFER IN | 00 F1 00 00 00 05 10 04 02 00 13
TXT: 16.04.2020, 16:06:12 | WAITING | <EOT><ACK><GS><NUL><SOH>
HEX: 16.04.2020, 16:06:12 | WAITING | 04 06 1D 00 01
TXT: 16.04.2020, 16:06:12 | TRANSMIT | <EOT><ACK><GS><NUL><SOH>
HEX: 16.04.2020, 16:06:12 | TRANSMIT | 04 06 1D 00 01
TXT: 16.04.2020, 16:06:12 | BUFFER IN | <NUL>p<NUL><NUL><NUL><ENQ><NUL><EOT><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:12 | BUFFER IN | 00 70 00 00 00 05 00 04 02 00 00
TXT: 16.04.2020, 16:06:12 | RESULT | <EOT><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:12 | RESULT | 04 02 00 00
TXT: 16.04.2020, 16:06:12 | WAITING | <ETX><ENQ>Ç<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | WAITING | 03 05 C7 00 01
TXT: 16.04.2020, 16:06:12 | TRANSMIT | <ETX><ENQ>Ç<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | TRANSMIT | 03 05 C7 00 01
TXT: 16.04.2020, 16:06:12 | BUFFER IN | <NUL>q<NUL><NUL><NUL><ENQ><NUL><ETX><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:12 | BUFFER IN | 00 71 00 00 00 05 00 03 02 00 00
TXT: 16.04.2020, 16:06:12 | RESULT | <ETX><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:12 | RESULT | 03 02 00 00
TXT: 16.04.2020, 16:06:12 | WAITING | <EOT><ENQ>ö<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | WAITING | 04 05 F6 00 01
TXT: 16.04.2020, 16:06:12 | TRANSMIT | <EOT><ENQ>ö<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | TRANSMIT | 04 05 F6 00 01
TXT: 16.04.2020, 16:06:12 | BUFFER IN | <NUL>r<NUL><NUL><NUL><ENQ><NUL><EOT><STX><NUL>õ
HEX: 16.04.2020, 16:06:12 | BUFFER IN | 00 72 00 00 00 05 00 04 02 00 F5
TXT: 16.04.2020, 16:06:12 | RESULT | <EOT><STX><NUL>õ
HEX: 16.04.2020, 16:06:12 | RESULT | 04 02 00 F5
TXT: 16.04.2020, 16:06:12 | WAITING | <EOT><ACK>%<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | WAITING | 04 06 25 00 01
TXT: 16.04.2020, 16:06:12 | TRANSMIT | <EOT><ACK>%<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | TRANSMIT | 04 06 25 00 01
TXT: 16.04.2020, 16:06:12 | BUFFER IN | <NUL>s<NUL><NUL><NUL><ENQ><NUL><EOT><STX>ÿÿ
HEX: 16.04.2020, 16:06:12 | BUFFER IN | 00 73 00 00 00 05 00 04 02 FF FF
TXT: 16.04.2020, 16:06:12 | RESULT | <EOT><STX>ÿÿ
HEX: 16.04.2020, 16:06:12 | RESULT | 04 02 FF FF
TXT: 16.04.2020, 16:06:12 | WAITING | <EOT><ENQ>û<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | WAITING | 04 05 FB 00 01
TXT: 16.04.2020, 16:06:12 | TRANSMIT | <EOT><ENQ>û<NUL><SOH>
HEX: 16.04.2020, 16:06:12 | TRANSMIT | 04 05 FB 00 01
TXT: 16.04.2020, 16:06:13 | BUFFER IN | <NUL>t<NUL><NUL><NUL><ENQ><NUL><EOT><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:13 | BUFFER IN | 00 74 00 00 00 05 00 04 02 00 00
TXT: 16.04.2020, 16:06:13 | RESULT | <EOT><STX><NUL><NUL>
HEX: 16.04.2020, 16:06:13 | RESULT | 04 02 00 00
TXT: 16.04.2020, 16:06:13 | BUFFER IN | <NUL>ò<NUL><NUL><NUL><ENQ><DLE><EOT><STX><NUL>7
HEX: 16.04.2020, 16:06:13 | BUFFER IN | 00 F2 00 00 00 05 10 04 02 00 37
TXT: 16.04.2020, 16:06:14 | BUFFER IN | <NUL>ó<NUL><NUL><NUL><ENQ><DLE><EOT><STX><STX>
HEX: 16.04.2020, 16:06:14 | BUFFER IN | 00 F3 00 00 00 05 10 04 02 02 87
Viele Grüße
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