General Specification Electrical Function gmw3110 General Motors Local Area Network Enhanced Diagnostic Test Mode Specification

Variable/Meaning 
Values 
Req_Index 
This is a counter which is used as an index into the array of requested DPIDs 
when trying to determine if all DPIDs in the request are valid.
 
0 to PDS_length 
PDS_Index 
This is a counter which is used as an index into the PDS when modifying the 
DPIDs stored in the PDS. It is also used as an index into the array of supported 
DPIDs when determining if all DPIDs in the request are supported.
 
0 to max of either 
PDS_length
or
num_supported_DPIDs 
Slow_Rate_Count 
The count refers to the minimum number of times that the Process_AA_Msgs() 
function shall be executed before sending out an item scheduled at the slow rate 
in the PDS.
 
Slow Rate/AA_Msg_Rate 
Medium_Rate_Count 
The count refers to the minimum number of times that the Process_AA_Msgs() 
function shall be executed before sending out an item scheduled at the medium 
rate in the PDS.
 
Medium Rate/ 
AA_Msg_Rate 
Fast_Rate_Count 
The count refers to the minimum number of times that the Process_AA_Msgs() 
function shall be executed before sending out an item scheduled at the fast rate 
in the PDS.
 
Fast Rate/AA_Msg_Rate 
Req_Sched_Rate_Count 
This is a local variable which is set to Slow_Rate_Count, Medium_Rate_Count, or 
Fast_Rate_Count based on the rate in the requested message.
 
Slow_Rate_Count, 
Medium_Rate_Count, or 
Fast_Rate_Count 
supported_DPIDs[] 
This is an array which contains all of the DPID numbers that the ECU supports.
 
N/A 
num_supported_DPIDs 
This is a variable which indicates the number of entries in the supported_DPIDs[] 
array.
 
Determined in ECU 
software based on the 
number of DPIDs 
supported