Is it better to use a Usb to Serial Adapter Cable or a PCI Serial Port Card when attaching a serial port modem to a computer that doesn't provide onboard serial ports?

I am leaning toward the USB to Serial Cable but do they work as well as a Serial Port Card? I have a US Robotics business class external serial modem that that I'd like to keep using for dialup internet connections.

Here are the devices I am thinking of using:

USB To Serial Cable: KINAMAX CB-RS232 (Prolific Chipset)
PCI Adapter Card: SYBA SD-PCI 15024 --single port chipset=SB16C1052PC1

Thank you

As always, "better" is a relative term. What may work best for you, won't for someone else. In my opinion, the USB serial cable gives you more flexibility, so I'd go for that. I've had good luck with them in the past.

Since you don't say what version/distro of Linux, or what your goal really is, it's hard to give details.

I also agree with TB0ne that USB serial port adapters work well. The Prolific chipset is well support and you should not have any problems with any recent distribution. Some newer adapter USB IDs may not be automatically recognized with older kernel modules.

Darn. I'd tend to think pci cards are better. Both ought to work if fully supported in drivers or kernels but...

In many cases I have have seen that the pci cards are more "native" to the system. They may even be shown in bios but a you should check bios first for pci cards. May have to configure them or even move slots where usb is pretty stable as to any usb slot and little config if it works it works sort of deal.



We used to use serial break out boxes to run automated machines. I don't think I have ever had them fail software wise. We switched to usb serial break out boxes and have had nothing but trouble software wise. Have to restart software where the serial boxes never failed unless they went bad.

What is a USB serial break out box?
USB serial adapters do have some limits. I have a hard time trying to get a GPS 1 PPS signal to lock up with gpsd.

Thanks for the feedback. I guess I'll try the USB To Serial Cable: KINAMAX CB-RS232. From what I've read it should be recognized by Linux as device ttyusb0 & use driver module pl2303.ko.

If that doesn't work properly, I'll buy an external USB controller based modem. From what I read, these two should work:

Rosewill RNX56USB (conexant cx93010 +cx20548) ..$25.00
Device: dev/ttyAMC0
Driver Module: cdc-acm.ko

US Robotics USR5637 ..$56.00

Maybe someday I'll step up to faster cable or DSL internet but for now dialup meets my needs. Thank you all again.

michaelk
Look at edgeport and digiboard cards and boxes. They have been making them for years.

http://www.digi.com/products/usb/edgeport.jsp#overview

Got it.. Thanks. I have multiple single port models attached to a hub. I use a simple labview application that connects to legacy data logging devices.