Interpreters Document

 The length of a routine is the total number of data 
bytes 
not
 including the 2 byte length and the 4 byte address. 
The first routine in the routine section will be referenced as routine number 1. The routine numbers are not 
included in the routines section of the Utility File. However, the routine number will be used in the Op-Code to 
call the routine. The tool will internally keep track of the routine numbers. If an Op-Code calls for routine 3, the 
tool will skip over the first two routines and return the data in the third routine. The tool will determine where 
each routine is located by using the routine lengths that precede each routine located in the routines section of 
the Utility File. 
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11 
Reprogramming Algorithm Overview 
The Reprogramming Algorithm is not required to be part of the Utility File. An application may store its 
Reprogramming Algorithm within the controller software instead of downloading them into RAM from the 
Utility File (routine section). Applications using Flash devices that do not store the Reprogramming 
Algorithm in the Utility File may copy their Flash I/O routines from controller software to RAM prior to 
reprogramming. This is necessary because it is not possible to execute from one Flash segment while 
trying to erase or write to another in the same Flash device. 
Using the Utility File to download the Reprogramming Algorithm offers a way to keep the reprogramming 
capability out of the controller software. This eliminates the danger of being able to write and erase 
controller software while executing normal operation controller software. The Reprogramming Algorithm is 
downloaded to the controller by the reprogramming tool per the Programming Instructions. The 
Reprogramming Algorithm is executed by the controller and should reside in Keep-Alive Memory if 
available. 
The Reprogramming Algorithm portion of the Utility File is flash device and hardware dependent. There is 
no distinction between subroutines that are hardware dependent and those that are flash device 
dependent. 
If additional suppliers exist for a reprogrammable controller or components of a controller, the Utility File 
must include all the necessary Reprogramming Algorithms for all suppliers of the controller and/or 
components. 
It is typically preferred to keep the size of the Reprogramming Algorithm as small as possible when the 
Reprogramming Algorithm is part of the Utility File. This may be necessary due to a lack of RAM available 
for reprogramming or Flash reprogramming event time limitations. Reprogramming requires the use of 
RAM that does not conflict with locations used in the normal operation download itself to execute the 
Reprogramming Algorithm and to buffer the new software and/or calibrations that will be reprogrammed. 
The ideal situation is to have a contiguous RAM region for each purpose, which takes advantage of the 
maximum downloaded message size. The Reprogramming Algorithm should be as efficient and fast as 
possible because of time constraints (i.e. an assembly plant reprogramming environment). 
The Reprogramming Algorithm typically consists of the following 5 basic functions: