VEGA INSYS Modem GPRS 5.0 User Manual
Page 92

GPRS General
INSYS GPRS 5.0 serial
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8.8.1.2 Data logger user data
A data logger message has the following setup:
Device ID
4 byte
2 x 8 bit for the digital inputs
2 byte
4 x 16 bit for the analogue inputs
8 byte
Checksum
1 byte
Total
15 byte
8.8.1.3 User data acknowledge of the control center
As an option, the data logger/control center software can be configured so that
for a data logger message an acknowledging message of the control center (user
data acknowledge) is sent.
Set-up:
Command (e.g. ACK)
1 byte
Checksum
1 byte
Total
2 byte
8.8.2 General data amount
For GPRS, such as for all IP-based transmission methods, the user data of the ap-
plication are packed into a TCP/IP message and sent to the remote terminal
(PUSH); the TCP/IP stack of the remote terminal (e.g. Windows) must acknowledge
each received TCP/IP message.
With GPRS, all data accumulated by the user from the IP level (incoming and out-
going) are calculated.
8.8.2.1 Transmission of user data without user data acknowledge of the remote termi-
nal
Application
/
GPRS modem
control center
Data: 15
TCP/IP PUSH: 40
Data: 0
TCP/IP ACK
: 40
Total: 95 byte