[docthal]

Looking for any advice on how to use the serial connection to load programs from a computer to the cnc memory. We have the correct cable, I have downloaded remoDNC and input the specifications for our machine, however there is no response from the CNC machine when I try to send it a program, and there is no response from the computer when I try to send a program from the CNC. I will also download predatorDNC to see if we have more luck with that program. Any advice or description as to how this is generally done would be appreciated.

[ZZZZ]

Maybe this will help

[Brian L]

You say you have a cable, has it previously worked on this machine and computer combo to connect? If not, I would suspect it is the cable, use the information ZZZZ provided to check your pin configurations and see what you have. I use a a cat 6 cable with adapters to DB25 and DB9 to make my cables. The adapters allow you to change the pin connections by not completely assembling them until you are sure you have the proper swap of connections.

I would double check the connection from the side of the mills electrical cabinet where the RS232 DB25 port is, there is a flat ribbon cable that comes over to the computer and connects. I re-wired mine with an RJ45 adapter and used a CAT6 cable to run a new wire to the front operators panel and mounted a port there, so I didn't have to wander around behind the machine to hook it up, just simpler for me.

Then if you follow the Utilities/Send/Receive protocol then it should work, start with sending from the machine to he computer, seems to be the easiest. check that you have the baud, parity and stop bits set correctly on both. Once you see some action, even if it's garbage coming out of the machine to the computer, you can usually adjust the settings on your com software and the machine to match and things should be good.

They make little tester/breakout boxes for RS232 comm checks.... I used to have one, little led lights that would tell you if a port was actually putting out anything, and you had a bunch of jumper wires you could plug and play until you had the right pin combinations, this was back in the day when you had to have about 7 or 8 wires connect, 2&3 had to be swapped, think it was like 8,16, and 20 had to be jumpered... any way, it was more complicated and took a bit of hair tearing out to get figured out when you had seven different brands of controls in the shop.

[docthal]

Thank you this is a great start, im going to read the pdf's you send me ZZZZ and check the cables.

We have purchased a new USB to serial DB25 adapter, along with a USB extension, since the last time we got this to work. There doesn't appear to be any way to wire this cable any differently than it is built, am I going to have to open up the casing or something?

[sportybob]

Hi Docthal, The RS-232 needs to be configured as a " null modem" cable. The send goes to receive and receive goes to send. This allows "communications, back and forth"

If I am understanding your reply correctly, you are running a USB cable to a usb serial adaptor which is connected to the 25 pin port on the machine. This would not work as the "cable is not a "null modem / cross over cable. you would need another cable from the serial adaptor to the machine port configured as a "null modem" cable.

Also if the control is not a SBC type, the original control I/O board does not support "FIFO" ( First In First Out ) buffer. you will need to turn off the FIFO buffers in your PC serial port advanced settings.

Sportybob