USB to Serial Adapters: The Struggle

Serial connectivity – you’ve got to be kidding me, right? No one uses that anymore! Well, guess again! Business Ethernet switches and many utility devices still utilize a serial connection. Consider that utility devices use not only the RS-232 serial that goes strictly between two devices as most consumers would know about, but also use a variant called RS-422 and RS-485 that are for multi-drop devices. These are not necessarily connected via a DB-9 connector as most people familiar with serial have seen. Regarding RS-232 though, the problem is that after the Windows XP era, serial became a nightmare to deal with. Laptops stopped having them, so you had to get a USB to serial adapter. And finding one that worked was a nightmare. At least for me it was. Drivers wouldn’t work and sometimes even if you found a driver that Windows was happy with, the device still wouldn’t work or would not work in some instances. Oh, and to continue on this complaint list, my Windows Internals utility for serial port monitoring stopped working. Its irritating to struggle to get basic connectivity and diagnosing capability to the devices you are hired to configure, maintain, and troubleshoot. A few years back, I found out some reasoning behind it. It ended up having to do with both the driver support being crap, the processor being crap, or the chipset used for the converter being crap and in some instances combinations. I found a document on it on the website where I bought my current and hopefully last USB to serial converter, a Thunderlinx.  They have a different document on selecting a good adapter, should the Thunderlinx not be one you want.  Should the link break, here is a copy I made of it.  And here is the device, the Thunderlinx.

I love this device.  It has always worked without exception.  It has the indicators for transmit and receive, a huge benefit to seeing if any communication is occurring.  It does not re-assign port numbers if you plug it into a different USB port, which some adapters do.  And the thing seems rugged.  I by accident dropped the adapter into water while it was powered up.  I got it out within a couple seconds, but had no damage.  I still use that adapter.  If you need an RS-232 adapter, I highly recommend this one.

As a side note, it appears as though drilling down into their website that redirects to US Converters, there is a lot of different reference on serial and MODBUS.