i'm having trouble with my serial port communication on an rs-232 connection in DOSBOX communicating with a FANUC CNC controller. I had the same software setup with an older machine on windows 7 and It wasn’t having issues with communicating. I am wondering if this problem could be due to software incompatibility between windows 7 and 10. DOSBOX is emulating a CNC communications program called POWERSTATIONS. This program is communicating with HARDINGE VMCII 600 CNC machine.

I have a SUNIX DEL2S00PL 2-port RS-232 PCI Express Powered Serial Board that i’m using for the RS-232 communication. (ATTN): The power supply is not connected to the 6pin on the serial board. This was the same with my previous setup in the windows 7 machine and the serial communications worked just fine. I have attached the DATA SHEET for the serial card.

Troubleshooting: Here are the first few things that I've tried.

Feedback loop (shorting out the pins) with rs-232 connection failed. Program communication went into a looping error
Checked all the cabling connection which where all working correctly
Tried switching the com ports that I was communicating on, which resulted in the same errors

Here what the terminal in DOSBOX is outputting:

Run 1:
Serial1: Errors: Framing 0, Parity 0, Overrun RX:210 (IF0:57), Break 0

Run2:

Serial1: Errors: Framing 0, Parity 0, Overrun RX:200 (IF0:41),TX:0, Break 0
Serial1: Errors: Framing 0, Parity 0, Overrun RX:200 (IF0:1),TX:0, Break 0
Serial1: Errors: Framing 0, Parity 0, Overrun RX:200 (IF0:0),TX:0, Break 0

Here is the code i’m running to start up the virtual serial ports and the program POWERSTATIONS.

My Serial port is configured as follows:
serial1=directserial realport:com1
serial2=disabled
serial3=directserial realport:com3
serial4=directserial realport:com4

Here is the code that runs the program:
mount c c:\dos

serial3=directserial realport:com3
serial4=directserial realport:com4
serial1=directserial realport:com1

c:
cd ps
ps

My CPU is configured as follows:
core=auto
cputype=auto
cycles=3000
cycleup=10
cycledown=20

Here is how my com ports are configured in windows:

Bits per second: 9600
Data bits: 7
Parity: Even
Stop bits: 1
Flow Control: None
Under advanced -- I have 128 bit FIFO buffers enabled

I was wondering if anyone would know the cause behind the COM communication errors problems and know a possible solution?

Thank you