Host Engineering Forum

General Category => Do-more CPUs and Do-more Designer Software => Topic started by: JoshChapman on February 17, 2021, 06:57:39 PM

Title: Receive SPC data to PLC?
Post by: JoshChapman on February 17, 2021, 06:57:39 PM

I need to interface a Mitutoyo digital indicator with SPC output into a BRX PLC. Has anyone done this? What is the best way?

Title: Re: Receive SPC data to PLC?
Post by: JoshChapman on February 18, 2021, 12:45:51 PM

I found this description (attached image) of the data from a Mitutoyo SPC port. It seems like it would be relatively easy to read directly off the pins. I also read somewhere that the data is in BCD number format but I don't really understand what that means. Anyone have any guidance?

Title: Re: Receive SPC data to PLC?
Post by: Bolt on February 18, 2021, 02:50:50 PM

I would think you need to run the SPC to a multiplexer, then that to PLC via RS232.

Title: Re: Receive SPC data to PLC?
Post by: ATU on February 19, 2021, 06:42:46 AM

You could probably do it with the high speed inputs and interrupts on the BRX. Take some work, but I think its fast enough if the BRX doesn't have very much going on when you want to take the measurement.  However, If they sell a serial or network converter, I would get that.

Title: Re: Receive SPC data to PLC?
Post by: Garyhlucas on February 19, 2021, 02:03:27 PM

BCD uses 4 bits per digit of a 16 bit word. So a 16 bit word has a range of 0 to 9999. A double word of 32 bits gives you 0 to 99,999,999. You decide where the decimal point goes.