Thomas Paine

Mits 500M control - need help with ladder array thingy

4 posts in this topic

Hey guys, first post!  Friends at Practical Machinist sent me over here b/c we were stumped.  

I have a Mitsubishi 500M control CNC machine.  There is a section of the ladders that i don't understand, and Mitsubishi couldn't help, and the OEM is defunct.  I do not have a hardcopy of the ladder circuits.

I have an output , [Y13], that i can't get to turn on because of an internal relay | M453 |       see pic 1

When i searched for relay M453, it seems as if it's in some sort of array function.  see pic 2

None of the relays from M448 thru M512 ever turn on.  I understand that all these are controlled thru this circuit, but i have no clue what is going on with the R registers, and how the heck these internal relays can be turned on.

Can you guys help explain?   Thanks!

CAM02029.jpg

CAM02030.jpg

Share this post


Link to post
Share on other sites

Welcome to the Forum,

The value in R2900 is minus 8431 which gives the bit pattern 1101111100010001 this is then MOV 'ed into  internal bit stores (M's).

The instruction [MOV R2900 M448 K4] moves the bit pattern generated by the value in R2900 into M448 through to M463, the K4 is the number of Nybbles (4bit groups) to mov, in this case 4 Nybbles (16 bits).

The question now is, what is actioning and putting the value into R2900?

I hope this helps

Steve

Share this post


Link to post
Share on other sites

wow thanks man, that makes perfect sense!  

I have no clue what is acting on R2900 thru R2903.  When i search R2900, it only comes up with this line seen above.  It seems embedded in another function, i'll have to find it and report back.  

 

Share this post


Link to post
Share on other sites

cool, you helped me figure out that the value of R2900 is equal to bit selection parameters line 1&2.

i guess i could force if i had to, but we won't go there yet.

 

CAM02034.jpg

ScreenHunter_07 Feb. 24 11.47.gif

ScreenHunter_08 Feb. 24 11.48.gif

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now