Hello guys, I'm new here so go easy on me .
Right I have many years AB experience but I am using the contollogix plc with RSLogix5000 programming software for the first time and I have a couple of questions/problems.
Firstly, the I/O scan is now asynchronous. If I am monitoring the same input to set 2 different latches in 2 different parts of my program, I assume I could reach the end of the "scan" and find one latch on and one off? Does this mean that I should move all my inputs to internal coils at the start of the program, and then move internal coils to real outputs at the end, to artificially create a synchronous scan? I wouldn't even think of doing this in PLC5, what do you guys do?
On the same point, I have an HMI linked to the PLC reading registers (status info to make screen items change colour). But as I am writing to these registers different info at different points in the program, the HMI screen objects flash, since they can access the register at any point, and not at the end of the scan. So likewise I have had to copy these registers at the end of the scan to another group read by the HMI to overcome this.
TIA
Dave G
Right I have many years AB experience but I am using the contollogix plc with RSLogix5000 programming software for the first time and I have a couple of questions/problems.
Firstly, the I/O scan is now asynchronous. If I am monitoring the same input to set 2 different latches in 2 different parts of my program, I assume I could reach the end of the "scan" and find one latch on and one off? Does this mean that I should move all my inputs to internal coils at the start of the program, and then move internal coils to real outputs at the end, to artificially create a synchronous scan? I wouldn't even think of doing this in PLC5, what do you guys do?
On the same point, I have an HMI linked to the PLC reading registers (status info to make screen items change colour). But as I am writing to these registers different info at different points in the program, the HMI screen objects flash, since they can access the register at any point, and not at the end of the scan. So likewise I have had to copy these registers at the end of the scan to another group read by the HMI to overcome this.
TIA
Dave G
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