Interpreters Document

Developers Note: 
 
This processing puts the requirement for the Interpreter into the hands of the developers who know what 
response codes are possible for a particular service request. When a developer is writing the Interpreter 
instructions the need for duplicate goto fields will be obvious and should not present any problems. 
Negative response processing
Utility File Example and Pseudo Code 
Following is the message structure and utility line for pseudo code example below. 
PositiveResponse 
ServiceID
$77
RequestMessage 
ServiceID 
$37 
NegativeResponse
ResponseID 
RequestID 
ResponseCode 
$7F 
$37 
$77 
Step 
Op-Code AC0 
AC1 
AC2 
AC3 
G0-G1 G2-G3 G4-G5 G6-G7 G8-G9 
12 
37 
00 
00 
00 
00 
77-1B 
41-17 
72-17 
77-18 
FF-15 
If
a PositiveResponse is received (ResponseServiceID is RequestMessageServiceID + $40). 
Use the first occurrence of the PositiveResponseServiceID ($77) to determine next step. 
(For this example the next step is Step 1B. )
Else
a NegativeResponse was received (ResponseServiceID is $7F). 
If
the NegativeResponseResponseCode equals the RequestMessageServiceID + $40.
Use the second occurrence of ResponseCode ($77), or the $FF Goto field if only 
one occurrence of ResponseCode ($77) is found, to determine next step. 
(For this example the next step is Step 18.)
Else
. 
Use the ResponseCode to determine the next step.
(
For Response Code $41 in this example, the next step is Step 17.)
Endif.
Endif
. 
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