labviewbeginner

thanks for the big explaining. Yes i tried it also with memcpy(pointer, datatable, sizeof(datatable)); But all the time labview crashes (just close without warning) when i start labview. I made me a test.vi: in this i just want to get the data from c to an array in labview. I did this: constant uint16 - bundle 7 times to get a cluster with 7 uint16 - then i made "initialize array" and wired the cluster in the above input and by the dimension size i made "constant int32" (this data type came automatically) then i wired it to the CFN. In the CFN i made "return type = numeric, signed 32-bit Integer" "arg1 = Adapt to type -> Handles by value". My C code is this: struct{ 7xuint16_t Integer}table; table datatable[16]; int32_t LV_DLL_EXPORT func(struct *pointer) { copy_to_datatable(); memcpy(pointer, datatable, sizeof(datatable)); return 1; } in the CFN the prototype is this : "int32_t func(void *arg1); And then i wired the CFN with an indicator array. This array i build like this in the FP : i took array. Then i took a cluster and put this into the array. In this cluster i put 7 numeric constant of the data type uin16. So now i have an 1D array with one cluster with 7 numeric constants. now i just raise the size of the array that i have 16 clusters in line. But still if i want to start the vi. it crashes without saying anything. So i think that i write or copy something into a position in the memory where something is written so that it should not be copied there. Or can you explain me what i make wrong? thanks anyway for the big help to understand it better. regards. labviewbeginner ps: i put labview screenshots attached

Thanks for the answer, 1) yes you are right. But at least i have to try it . 2) But the memory usage of the C file should be fitting to the labview vi. Am i right? So i need to know how i can solve this difference between the C 224-Bytes and the labview 224+x Bytes for the dataspace management. How can i do this? 3) ok thanks. So am i right that i need to use the CFN not the CIN? 4) ok if i have the struct and the function like above: struct{ 7xuint16_t Integer}table; table datatable[16]; (here is C allocating the memory for the array with struct of integers if i am right) int32_t func (struct *pointer) { copy_in_table(); (this copies my data into the table) pointer = datatable; (did you mean it like this? that i can give the pointer the data of the table, because C is using arrays as pointers as i read somewhere) return 1; } Is this correct? Because if you say yes i dont know why my Labview all the time crashes without any error warning. it just closes itself. Yes sorry for this i will stick to this forum. Thanks. LabviewBeginner

Hello, i have a problem. I am writing a C code and i have to edit an existing Labview code. My big problem is with the CFN that i dont know how to get the data from the array of structs with integer (array of 16 structs with 7 integer elements) into an array of cluster of 7 integers. I tried it with struct {..7 integer (each uint16_t)..}table; struct table[16]; "int32 func (struct *pointer)" and memcpy( pointer, table, sizeof(struct)*16); , and then my labview crashes without any error warning. And i found out via debugger from visual studio, that i think memcpy is saving his data into the memory of labview where it isnt allowed to save it. so my first question is: 1) if i make a numeric constant and bundle 7 types of it to one cluster and use "build array" and make all of this before the CFN, is the memory for this allocated and the value is "0"? Second: 2) how much bytes are allocated for this? How can i look how much bytes does an array of 16 cluster with each 7 uint16-integers need? 3) What is the difference between Call Library Function node and "call interface node" exactly? 4) If i have another three function in C which copies some data into the C array "table" how can i get the data from this "table" into Labview when i only have the possibility to return void, numeric or string?? Because as far as i know i need in Ansi C for the array of 16 structs with 7 uint16_t-Integers 224 Bytes (16*7*2Bytes) . Am i correct by this? I think the most problem is about the memory handling here. About help i am very grateful. Sincerly Labviewbeginner