BACnet MS/TP to BACnet/IP

Hello, I have questions.
I'm trying to connect Omron(Km-N1-bacnet) device with the ignition.
My device has RS-485 communication and BACnet MS/TP.
I found that ignition only has BACnet/IP connection.
I searched on the internet and found that I need BACnet MS/TP to BACnet/IP gateway device. I'm just studying about how to connect BACnet device with ignition. So it is kind of hard for me to buy the device.
Is there any other option or way to connect BACnet MS/TP with ignition without buying device ?

As a resource, I attached my Omron Device information link.

The website is in Japanese, I'm so sorry about that.

I also have DT-5019I USB2.0 convert to RS422/485 serial cable.
My Omron device has two function which are Modbus and BACnet.
I used DT-5019I USB2.0 converter to connect Modbus RTU with ignition.
It worked for Modbus but I think that DT-5019I don't have function to connect BACnet. Am I right ?
Here is the link of DT-50191

Thank you for your time. Have a nice day.

As MS/TP uses a serial connection, there is no way to connect an MS/TP device to Ignition without using an MS/TP to IP "converter." I've used some pretty cheap solutions off of Google searches with success. My personal favorite is Contemporary Controls. Very easy to set up, relatively cheap, and easy to find.