https://forge.codesys.com/forge/talk/CODESYS-V2/thread/afb32de10a/2020-02-27T21:40:27.771000ZRecent posts to Save array data in code segment2020-02-27T21:40:27.771000Z2020-02-27T21:40:27.771000ZIgor Petrovhttps://forge.codesys.com/u/igor-petrov/https://forge.codesys.com0690cda5564099d5831ed26b15cee008935d1e9b

<div class="markdown_content"><p>The generated code belongs to initialization section executed only once. Therefore intensive optimization in it is not important for the program speed.</p> <p>If you have few memory and really need to optimize code by size then you may try the next trick. I used it for 8051 system with tiny memory. </p> <p>1) You can declare string instead of BYTE array. For example: </p> <p>It have to generate compact string in code memory with compact mem copy function for initialization.</p> <p>2) There are 2 methods to use a string like an rray. A) Declare both the string and the array on the same address in 'M' memory; B) Make pointer to the array and set it to ADR of the string. </p> <p>Regards </p></div>

2020-02-27T21:40:26.125000Z2020-02-27T21:40:26.125000Zjan233321https://forge.codesys.com/u/jan233321/https://forge.codesys.com391439537a79890ffc303a8dc22ed3cc417beb21

<div class="markdown_content"><p>Hi all,</p> <p>I'm trying to create constant arrays of bytes. If I use global variables and VAR_CONSTANT, it looks like:</p> <p>code in ST:</p> <p>generated code:</p> <p>255 times. If you have more than 1 array then more times... .</p> <p>This code is not very optimised, it is consuming a large amount of code memory (1 array item needs 12 bytes of code memory).</p> <p>Does exist any possibility to create this array directly in program memory segment (in flash - any pragma)? Next step is to create one small loop to copy data from flash to ram.</p> <p>Thans</p> <p>Jan</p></div>