Posted 7 Apr 2021 (edited) Hello everybody, i have some uncertainties going through my head. i am fairly new in PLC word, graduated last year, last 12 month i did project on Siemens PLCs, but now i have to expand my view with Mitsubishi. 1. i am working on project with several conveyors. for each conveyor type i have FB fairly similar to my FB in siemens. For all conveyor i am using same sdt containing 32 bits. So a have array[0..20] of said sdt. But in fb i was not able to copy item from array, through input var containing index of that item to vocal variable, which i wanted to write back to the array at the end of fb. I tried different approach -> using item from array *** input/output. When monitoring item from array i can see, that variables i change in got2000 panel are in fact changing. But when i monitor fb itself, those same variables are not changing. i reworked this fb several times, for example when i found out that FB variables FB FXcpu cannot be set as retain so i would like to use it and i see no other way than make this fb work. :D 2. Is there possibility to us FB in another FB? I remember that i read some restriction about this, but now, i cannot find it. Thank you everybody for your responses Edited 7 Apr 2021 by naj.keclv more specific title Share this post Link to post Share on other sites
Posted 8 Apr 2021 1. Can you attach a small example project. then we can take a look at where you are going wrong. 2. Yes it is possible to use a FB in a FB in a FB etc, If you want to use a label from inside a FB just use the nameFB.nameFB.labelname Share this post Link to post Share on other sites
Posted 9 Apr 2021 Hello again, so as in/out i use db_MVT[2] (it is 32 bit) cyan blue in first picture, and variable HS_L of db_mvt[2] is currently logic 1. But in function block it does not reflect. As when i monitor fb with correct insatance it shows logic 0. Share this post Link to post Share on other sites
Posted 9 Apr 2021 strange, but it is defined as an inout. could it be that it is reset in the FB itself ? Share this post Link to post Share on other sites
Posted 9 Apr 2021 no, the variable is only used as read. But i might delete array of sdt and replace it with several sdts. Because i do not have good experience with arrays and gx works 2. :D and those two for loops i will just rewrite manually as the array itself is not that big, only twenty elements. or i will use of index registers. Share this post Link to post Share on other sites
Posted 12 Apr 2021 So apparently, gx works 2 cannot handle an instance of array as an input to function block. Share this post Link to post Share on other sites
