Serial to USB back to Serial... can I do it?

[jujumaster89]

All,
I'm new to this forum and not an electrical engineer. I am trying to get a Serial cable from my telescope connected to a controller inside an enclosure. The serial connector will not fit and cutting a larger opening is something I would like to avoid. A USB cable would fit into the enclosure.

Can I use 2 serial/usb adapters back to back with a short USB cable in between so that my through-connection is usb while the ends remain serial?

Thanks,
Ian

 

[Harald Kapp]

Welcome to EP.

That's not (easily) possible for several reasons:

1. USB is a master slave bus whereas a RS232 serial interface doesn't distinguish master and slave. USB to serial adapters only work when there is a suitable driver on the master (PC) side.
2. You'd need a power supply for the USB side of the wiring

The easy way around this is by opening the serial connector (am I right in assuming it's a 9 pin D-sub connector?) on one end of the serial cable. De-solder the wires, making notes which wire goes to which pin (if you're lucky only 3 wires are involved. Maybe more if hardware controls are used). Feed the now loose end through the opening in the enclosure. Re-solder the wires according to the scheme you noted when de-soldering. Re-attach the housing of the connector and you're set.

 

[Externet]

One like these ?
----> https://duckduckgo.com/?q=usb+to+serial+adapter&t=canonical&iax=images&ia=images

 

[Harald Kapp]

Those won't work. You can't connect two of them back to back on the USB side. Plus what I wrote in post #2.

 

[jujumaster89]

Thanks for the insight. I may just cut the cable and solder it back together rather than trying to open up the connector. It seems like it would be hard to cut open.

Of course, if this doesn't work (or I'm not capable) I'll find some other way. I do have less elegant options that would not require cutting the cable.

Thanks,
Ian

 

[Nanren888]

Serial, RS232C?, connectors are cheap. You could likely consider making up your own cable.