Doc. Title
Author
Page of Pages
ST300/340 OPERATION MANUAL
– LATAM
HG.Park
91 of 146
Concerning
Doc. No.
Rev.
Date
Features and How to set parameters
1.41
26 May. 2015
Suntech International Ltd.
Confidential Document
6-6. Keep-Alive Report
A typical GSM/GPRS service provider in any countries has its own corporate policy restricting connection time of
device with the GSM/GPRS networks only at an interval if device does not communicate with its server for a long
time, which is 1 hour, for instance. The time length varies depending upon such service provider. Please check it
by asking your GSM/GPRS service provider this question in your country.
In a case that there has not been any communication between a device and its server for such a time period, the
GSM/GPRS service provider would not provide GSM/GPRS service for the device temporarily. To avoid such a
case, device sends the server this
‘Keep-Alive’ Report at an interval, ‘T4’ (‘Keep-Alive’ interval named in ‘SyncTrak’
and in this document), which is shorter than the 60 minutes. User of the device may adjust the value of
‘T4’ as
desired.
This report is intended to mean that the device is still alive and ready for any possible communications with the
server for that long time (
‘T4’) even though the device does not interact temporarily with the server.
6-6-1. Normal
All Models
HDR
DEV_ID
Field
Marks
Meaning
HDR
“ST300ALV” Header of Alive report.
DEV_ID
9 char
Device ID.
<Example>
ST300ALV;100850000
6-6-2. Zip
Field
Marks
Meaning
HDR
0x14
Alive Report header (1 byte).
DEV_ID
5 bytes
Device ID:
BCD format.
If the Device ID is 123456789, this field will be filled with 0x12, 0x34, 0x56,
0x78 and 0x90.
<Example>
Original String :
ST300ALV;600850777
Zip Packet
Filed name
Zip data
Comment with string data
STX
0x02
PKT_LEN
0x00 0x06
HDR
0x14
“ST300ALV”
DEV_ID
0x60 0x08 0x50 0x77 0x70
“600850777”
ETX
0x03
