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Where does the momentum come from? from the PLC ? it can appear in the period between the PLC requests – then the PLC program requires a delay of this pulse for the network variable. Or did you mean something else ?
Since the xml file is used to save the dat file data and transfer copies, the system itself works with the dat file
I can’t check it, because I don’t have a PLC on my hands. I downloaded version 2.3.4 And renamed it libplctag.so.2.3.4 v libplctag.so and put on the path /usr/lib I do not know how true this is for working on Linux. Version 2.3.5 has already appeared on the developer’s website
https://github.com/libplctag/libplctag/releases
The library calls exactly libplctag.so Please write, will it work or not ? And if anything, write to the mail with the computer code, so that I can make a key.
libplctag.so this library should be located either in the /lib folder and probably should be registered in the system (I don’t remember the nuances now) But that’s not all, in my library there should be a call to the libraries of Linux versions, the build should be under Linux
My Raspberry uses a BCM2835 processor which is an ARMv7 Processor rev 4 (v71) I used the
cat /proc/cpuinfocommandfedex
Possible. The developer has experimental builds for libplctag_2.3.4_linux_arm6hf_EXPERIMENTAL.zip and libplctag_2.3.4_linux_arm7l_EXPERIMENTAL.zip
If any of the builds are suitable for Raspberry, I can try to rebuild the driver for them. But I unfortunately have nothing to test on. I have already returned the PLC and I do not have access to it. If you can arrange remote access to the PLC, I can try to check this possibility.Bus 001 Device 006: ID 1a86:7523 QinHeng Electronics HL-340 USB-Serial adapter
Bus 001 Device 005: ID 1a86:7523 QinHeng Electronics HL-340 USB-Serial adapter
Bus 001 Device 004: ID 067b:2303 Prolific Technology, Inc. PL2303 Serial PortI didn’t pay attention, you have a cheap USB-RS485 converter, I have the same ones.
But I have only 3 pieces installed. And at the time of reboot, they can change their numbers, for example, from /dev/ttyUSB0 to /dev/ttyUSB1, which is unacceptable for the system to work.
So I apply the Udev rules so that they are named as I want, regardless of what number the device received.dmesg | grep usb
[ 2.031971] usb 1-1.2: new full-speed USB device number 4 using dwc_otg [ 2.164990] usb 1-1.2: New USB device found, idVendor=067b, idProduct=2303, bcdDevice= 3.00 [ 2.165006] usb 1-1.2: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 2.165015] usb 1-1.2: Product: USB-Serial Controller [ 2.165025] usb 1-1.2: Manufacturer: Prolific Technology Inc. [ 2.262025] usb 1-1.3: new full-speed USB device number 5 using dwc_otg [ 2.395529] usb 1-1.3: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.54 [ 2.395550] usb 1-1.3: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [ 2.395559] usb 1-1.3: Product: USB2.0-Serial [ 2.491981] usb 1-1.5: new full-speed USB device number 6 using dwc_otg [ 2.625521] usb 1-1.5: New USB device found, idVendor=1a86, idProduct=7523, bcdDevice= 2.54 [ 2.625539] usb 1-1.5: New USB device strings: Mfr=0, Product=2, SerialNumber=0 [ 2.625549] usb 1-1.5: Product: USB2.0-Ser! [ 2.944434] usbcore: registered new interface driver usbserial_generic [ 2.944504] usbserial: USB Serial support registered for generic [ 2.953464] usbcore: registered new interface driver ch341 [ 2.953554] usbserial: USB Serial support registered for ch341-uart [ 2.965080] usb 1-1.3: ch341-uart converter now attached to ttyUSB0 [ 2.975967] usb 1-1.5: ch341-uart converter now attached to ttyUSB1 [ 3.042552] usbcore: registered new interface driver pl2303 [ 3.042659] usbserial: USB Serial support registered for pl2303 [ 3.058874] usb 1-1.2: pl2303 converter now attached to ttyUSB2 [ 3.955816] usbcore: registered new interface driver brcmfmac [13594.241044] pl2303 ttyUSB2: usb_serial_generic_read_bulk_callback - urb stopped: -32see the output of the command
usb 1-1.3: ch341-uart converter now attached to ttyUSB0
usb 1-1.5: ch341-uart converter now attached to ttyUSB1
usb 1-1.2: pl2303 converter now attached to ttyUSB2Here 1.3 is the number of the USB port on the Raspberry and /dev/ttyUSB0 what is the port number received by the device
Run the
dmesg | grep usb
command and look at the output, there you will find the port number to which the USB-RS485 is connected, and in your case, most likely the serial number of the device. Cheap devices don’t have a serial number and can only be linked to the USB port number on the RaspberryUDEV rules must be applied when you connect two or more USB-RS485 devices. In your case, it will most likely be /dev/ttyUSB0
In general, by default, all ports have the form /dev/ttyUSBx, where instead of x, the number is from 0 and on. But if you have two or more devices, sometimes the numbers change. So that the number does not change and the Udev rule is made and the device has the same name, but it is bound to a specific port via symlink.
Use an online translator. The rules can bind the USB-RS485 converter to a specific port name, depending on which USB port you connect the device to. Then the port name will look like /dev/mydev/Com1 or Com3 and so on
But this does not solve the problem of saving the pulse to the channel database when writing once per minute.
Will the TP timer be enough for you, similar to how it is implemented in a PLC?
Calling the formula Tp (Val(414), 10000) number of the monitored channel 414, time in milliseconds.
When 1 appears in channel 414, the timer output will turn on, after 10 seconds it will turn off for this example. The timer starts working on the signal edge, no need to hold 1 in the controlled channel.The Ticks formula is used in all the timers I’ve done. The formulas must be added to the Formula Reference.
