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10.2 Communication Transaction Examples
10.2.1 Transaction A Example
Host requests 9 bytes of data beginning at hexadecimal memory address 1000
H
from the AW400 at data-link
address 03:
1. Host sends interrogate message:
01111110 11100011 00001001 00000000 00010000 11111100
SOH Command NUM LO ADD HI ADD LRC
+ I.A.
2. AW400 sends response message:
01111110 00100011 00001001 00000000 00010000 XXXX XXXX XXXX LRC
SOH Command NUM LO ADD HI ADD Data 1 ………..Data 9
+ I.A.
10.2.2 Transaction B Example
Host sends two bytes of new data, to be loaded into the AW400 at data-link address 03 beginning at
hexadecimal memory address 1000
H
:
1. Host sends change message:
01111110 10100011 00000010 00000000 00010000 00001000 00001100 11001001
SOH Command NUM LO ADD HI ADD Data 1 Data 2 LRC
+ I.A.
2. AW400 sends response message:
01111110 00100011 00000010 00000000 00010000 00001000 00001100 01001001
SOH Command NUM LO ADD HI ADD Data 1 Data 2 LRC
+ I.A.
3. Host sends acknowledge message:
01111110 10000011
SOH Command
+ I.A.
4. AW400 performs the change requested at end of the current program scan.
Note: Database address table is shown at the end of this section.