# USB-RS232 **URL:** \ **Category:** Miscellaneous\ **Created:** [May 8, 2020, 2:32pm UTC](https://community.sparkfun.com/t/usb-rs232/39565 "2020-05-08T14:32:33Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![ronf1964](https://avatars.discourse-cdn.com/v4/letter/r/977dab/32.png) [@ronf1964](https://community.sparkfun.com/u/ronf1964)\ **Post date:** [May 8, 2020, 2:32pm UTC](https://community.sparkfun.com/t/usb-rs232/39565/1 "2020-05-08T14:32:33Z")
I am in need of a converter that converts USB to RS232 signal levels. I want to replace an older Serial touchscreen on my CNC machine with a newer one that is USB. I cannot install a driver on the controller. IS there anything out there that could be used? ---
**Author:** ![TS-Brandon](https://avatars.discourse-cdn.com/v4/letter/t/cc9497/32.png) [@TS-Brandon](https://community.sparkfun.com/u/TS-Brandon)\ **Post date:** [May 8, 2020, 4:55pm UTC](https://community.sparkfun.com/t/usb-rs232/39565/2 "2020-05-08T16:55:50Z")
The most direct component we have is a USB to RS232 converter cable: [https://www.sparkfun.com/products/11304](https://www.sparkfun.com/products/11304) ---
**Author:** ![brow](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/brow/32/6116_2.png) [@brow](https://community.sparkfun.com/u/brow)\ **Post date:** [May 8, 2020, 5:28pm UTC](https://community.sparkfun.com/t/usb-rs232/39565/3 "2020-05-08T17:28:26Z")
The problem is going to be that there isn’t a USB host. When a USB device is connected to another, there’s a bit of discussion between the two. They agree on things like data rates, device addressing, and the device class (are you a mass storage device, a printer, a keyboard, sound card, etc?). The CNC controller has a serial input so it can’t serve as the host. The touch panel also can’t be the host; it’s a display and human interface device. I’m not aware of an aftermarket interface or adapter that could make these work together. ---
**Author:** ![languer](https://yyz1.discourse-cdn.com/sparkfun/user_avatar/community.sparkfun.com/languer/32/2998_2.png) [@languer](https://community.sparkfun.com/u/languer)\ **Post date:** [May 8, 2020, 11:48pm UTC](https://community.sparkfun.com/t/usb-rs232/39565/4 "2020-05-08T23:48:43Z")
If the new screen USB interface is merely a USB serial connection (i.e. like a FTDI converter) then you may be able to use an Arduino with built-in USB serial to do the conversion between the two. If the new screen USB interface is a low-level USB device (i.e. HID) then perhaps using something like an RPi in between the screen and the CNC should work.