I've been reading a LOT of the past topics, and A-B Knowledgebase, on the FFL/FFU instructions, but I still don't understand a couple of things.
Can you use the FFL instruction by itself, or is it mandatory to use the FFU with it as a pair? As long as you reset the ".POS = 0" when the FFL is done, then wouldn't it just continue to overwrite the existing data elements within the array?
If you have to use the FFU instruction, then do you also have to reset the .POS of the FFU?
Is the length of the FFU the same as the FFL, or is it the length of the DESTination? I will be unloading a 30 element DINT array into a single DINT waste tag, so I don't care if it is overwritten.
Here's what I have set up so far in the FFL/FFU instructions. Screen captures can be done if needed.
FFL:
Can you use the FFL instruction by itself, or is it mandatory to use the FFU with it as a pair? As long as you reset the ".POS = 0" when the FFL is done, then wouldn't it just continue to overwrite the existing data elements within the array?
If you have to use the FFU instruction, then do you also have to reset the .POS of the FFU?
Is the length of the FFU the same as the FFL, or is it the length of the DESTination? I will be unloading a 30 element DINT array into a single DINT waste tag, so I don't care if it is overwritten.
Here's what I have set up so far in the FFL/FFU instructions. Screen captures can be done if needed.
FFL:
Source A450 KW Total
FIFO A450 KW Total Array[0]
Control A450 FFL Control[0]
Length 30
POS 0
FFU:FIFO A450 KW Total Array[0]
Control A450 FFL Control[0]
Length 30
POS 0
FIFO A450 KW Total Array[0]
DEST A450 FFU Destination
Control A450 FFL Control
Length 30
Position 0
I'm copying the Total Array to a buffer array each time, and sorting that to perform other functions, so if I don't have to unload the FIFO, then it would make things a lot easier.DEST A450 FFU Destination
Control A450 FFL Control
Length 30
Position 0