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AC75_ATC_V01.002

Page 282 of 569

10/30/06

Confidential / Released

This section applies only to the Socket service using the UDP protocol. The example shows how to read UDP

packets if the buffer of the host application can handle only a few bytes. There are two datagrams available for

reading. 

Buffer size: 6 bytes

Datagram A = 18 bytes (content "THIS_IS_DATAGRAM_A")

Datagram B =   3 bytes (content "NEW")

^SISR: 0,1

Service profile 0 is configured for Socket service and UDP. The URC

notifies host that data is available for reading.

at^sisr=0,6

The host requests to read 6 bytes.

^SISR: 0,6,12
THIS_I 

The first 6 bytes of datagram A are confirmed and transmitted. Another

12 bytes are still available. 

OK

at^sisr=0,6

The host requests to read the next part of 6 bytes.

^SISR: 0,6,6
S_DATA 

The next 6 bytes of datagram A are confirmed and transmitted. Another

6 bytes are still available. 

OK

at^sisr=0,6

The host requests to read the next part of 6 bytes.

^SISR: 0,6,0
GRAM_A 

Last part of datagram A was received, no remainder is left. 

OK

at^sisr=0,6

Again, the host requests to read 6 bytes. This time, the request refers to

datagram B which has only 3 bytes. As the read datagram is smaller

than the size requested by the host, the response does not include the

^SISR: 0,3
NEW 

3 bytes are confirmed and transmitted. Datagram B was properly

received. 

OK