Mitsubishi fx1s

[fithol]

Good evening,
Let me introduce myself, I am a 70 year old retiree, my name is Guy
During my professional life I programmed plcs of various brands without too much problem, but the programs were simple.
Today, I find myself with a mitsubishi fx1s on a small packaging machine that I would like to put in order.
In the code there are two entries X0 and X1 witch do not appear in the ladder. I'm lost, these two inputs are used to detect a contrast mark on the packaging film.
If a member is ready to take a look I will send them the code
I use GX developer
Thanks in advance

Guy

 

[Blenderhedd]

IIRC on the FX1s X0/X1 can be used as up/down high speed counters. We used to read linear encoders that way.

 

[parky]

Not absolutely sure about the FX1 but most FX have interrupts these can be used as high speed counters and possibly as interrupts, if these used within the program then they are probably used in interrupt mode, however, if used as High speed inputs to the high speed counters then there will not be in the program, if counters C235 & upwards are in the program (normally driven by M8000 (always on bit) then they are used as high speed counting, if not then probably interrupt. i.e. when either X0 or X1 goes true (positive edge trigger) it will jump to a sub program i.e. interrupt the main program to do what ever is required.

 

[parky]

Just had a look the FX1S can use both high speed counters & interrupts
C235 & C236 are the high speed counters for incremental counts, if using interrupts then there will be a jump to a pointer i.e. P101 (X0) then after a FEND instruction you will see a P101 in the left hand side that is where the code is plus it is terminated with a RET instruction.

 

[parky]

If you post the code I can have a look or if you prefer send me a private message with your email address & I will reply with mine so you can send the file.
What IDE are you using GXDeveloper or GXWorks

 

[parky]

Attached are some info on high speed counters & interrupts
note: these are not practical examples just an idea how they work.
One picture is of the counters & associated inputs.
The other is how Mitsubishi does high speed counting or the use of interrupts
Note: the print of code is not practical as both ways are shown i.e. enabling a counter (here i use M8000 always true flag but could use some other contact to turn it on/off) X0 cannot be used in the program as with this instruction it is tied to the counter C235 (note: c235- C237 are for X0 to X2).
The other logic is how they enable hardware interrupts, for example EI is enable interrupts, the pointer I001 after the FEND instruction is for X0
i.e. I001 is X0 interrupt on rising edge, I000 is X0 on falling edge
I1001 is X1 & so on.