Hi all
Ran into this little problem at work, and wondred if anyone could give me some info about it.
For reasons best left alone, it was required that a machine operator was able to enter a 7 charachter alpha-numeric string into a PLC via the HMI on that machine. To keep things simple, it was decided that it was only required that the operator should enter the 5 digit number portion of the string, the two alpha prefix characters being entered by a higher authourity on a standalone PC. This caused me a headache as....
The HMI already in place is a panelview 1000. This is a headache as it is the old style PV (CRT screen, not programmable with PanelBuilder32). I then moved on to sticking an extra HMI onto the machine, a PV550. My problems arose when i tried to set up the numeric entry system. As it needed a 5 digit number, a 16 bit integer was not enough. I tried setting the data type on the numeric entry as DINT, but on verify it said "object/data type mismach" (implying that a DINT isn't numeric?!?!). I then tried with REAL, but the resultant number in the PLC was not correct). My questions are........
1. What is a DINT (numeric?) and why wouldn't my PV allow it?
2. Why did the REAL have some kind of bias on it?
3. If the dint would work, and i gave it a tag address of n3:0, would it automatically place the dint in N3:0 and n3:1.
4. Does anyone know if it would be possible to enter a charachter string/32bit integer into the OLD Panelview 1000 HMI?
I eventually just settled for charchter string data type. It wasn't ideal (for reasons i'll leave alone) but it does the job.
Sorry about the big and unnecessary description, but i know that most questions get a response of "What are you trying to do?", so i thought i'd get that bit out of the way.
Thanks in advance for your help, and i'm using PLC/SLC's with this PV550.
All the best
Guy
Ran into this little problem at work, and wondred if anyone could give me some info about it.
For reasons best left alone, it was required that a machine operator was able to enter a 7 charachter alpha-numeric string into a PLC via the HMI on that machine. To keep things simple, it was decided that it was only required that the operator should enter the 5 digit number portion of the string, the two alpha prefix characters being entered by a higher authourity on a standalone PC. This caused me a headache as....
The HMI already in place is a panelview 1000. This is a headache as it is the old style PV (CRT screen, not programmable with PanelBuilder32). I then moved on to sticking an extra HMI onto the machine, a PV550. My problems arose when i tried to set up the numeric entry system. As it needed a 5 digit number, a 16 bit integer was not enough. I tried setting the data type on the numeric entry as DINT, but on verify it said "object/data type mismach" (implying that a DINT isn't numeric?!?!). I then tried with REAL, but the resultant number in the PLC was not correct). My questions are........
1. What is a DINT (numeric?) and why wouldn't my PV allow it?
2. Why did the REAL have some kind of bias on it?
3. If the dint would work, and i gave it a tag address of n3:0, would it automatically place the dint in N3:0 and n3:1.
4. Does anyone know if it would be possible to enter a charachter string/32bit integer into the OLD Panelview 1000 HMI?
I eventually just settled for charchter string data type. It wasn't ideal (for reasons i'll leave alone) but it does the job.
Sorry about the big and unnecessary description, but i know that most questions get a response of "What are you trying to do?", so i thought i'd get that bit out of the way.
Thanks in advance for your help, and i'm using PLC/SLC's with this PV550.
All the best
Guy
