Jonesy alluded to a possible suggestion. Make your 'main' as tight as possible (inluding safety issues) and the subroutine call(s) handle the work load. This essentially reverses the main/subroutines relationship. To use an warn cliche, think outside the box.
I constructed something similar...
We used Proset 200 to upgrade a press in a Kodak plant. For starters, the bios of the Panelview HMI wasn't correct - this we found out only after much rending of hair. The result of bios mismatch was incorrect communications with the PLC which resulted in parameters and recipes not being saved...
I have found that converting files to .pdf format very useful. For example, I can send CAD diagrams to clients who may not have access to a CAD program.
I searched for free conversion utilities online and found only shareware which placed a huge "Demo" banner across the output (see...
Let me preface this by saying that I am not a qualified PEng. I have at times been called an "Applications Engineer". That's a title that seems be generally understood as someone narrowly qualified within a specific engineering field. I am not comfortable with even that title - I agree...
TIA;
Sounds like a job for a macro program. I've recently installed a freeware program called Quick Macros from: http://download.com. Do a search on "macros" and you'll find it no problem
I haven't had a chance to use it much, but it looks pretty good and might be just what you're...
Pap;
Seems to me that the easiest part of your problem is the hardware interface - writing a Modbus protocol driver from scratch will be a tedious business. I've done this for the Omron Host Link and Allen-Bradley DF1 protocols and i recommend finding a pre-written (and debugged) library if at...
Communicating to A-B processors seems to be an issue.
I wrote a subset of the DH+ protocol (in C) based on A-B's own documentation. The intent was to read and write to a few registers in an SLC 1500, which it does well enough. A few years ago i wrote the Omron Host Link protocol (also in C) and...
MacBeth is right. It is false economy to hang multiple functions off of single actuator inputs. Not only will this confuse the operators, but much worse, you'll find yourself in front of a board of inquiry because somebody found a combination of your 'clever' inputs that you didn't think about...
Steve;
Thanx for the web site address. I already know that the USB will work with the RS232 DF1 protocol - as long as you don't try to 'auto-configure' (in my case anyway). My new laptop doesn't have PCMCIA slots either. I would probably balk at the price of the 1784-PCMK card anyway. In the...
In checking catalogs, i find steppers with different volt/amp configurations producing the same torque. The configurations produce the same wattage values so this makes sense, however, i don't know which to select for a given application.
For example, from the Sanyo Denki StepSyn catalog (NEMA...
I recently bought a new laptop and found the same problem - no RS232 port. It's all been taken over by USB and firewire. On checking with our A-B distributor, i was told that the USB will not drive the PIC because there is no power out of the USB port for the PIC box. I have since seen products...
DDE is a bit slow. OPC was set up for just such (high speed) peripheral applications. RSLinx has a 'single node' (local) version which would allow you to tie into your PLC for a relatively cheap (for A-B) price of $395 US...
In southern Ontario (as i am) the Koyo/Direct camp has less support than in the US of A. This is TI stuff which seems to have a greater following south of the border (too bad really, i enjoy the 'stage' programming myself). You'll find less support than either A-B or Omron which are considered...