Generally about the serial port card.
A serial port card is an easy and reliable way of establishing a serial RS232, RS485 or RS422 port in a computer. Usually a serial port card is used for adding a serial RS232 COM port in a computer which can be used for connecting a variety of serial RS232 devices, however a serial port card can also be used for creating a RS485 or RS422 port.
Typically a serial port card is either a PCI serial port card or a PCMCIA serial port card, however the new standard replacing the PCMCIA serial port card is called a serial ExpressCard which is smaller than the PCMCIA serial port card and is being used in all newer computers sold today.
A PCMCIA serial port card is the most popular and most used serial port card, probably because it is easy to insert and start using in any desktop or laptop computer with a standard PCMCIA serial port slot. However the new ExpressCard serial port card mentioned earlier is taking over.
After the PCMCIA serial port card the PCI serial port card is the next most popular serial port card. The PCI serial port card is a bit harder to install than the PCMCIA serial port card, since the PCI serial port card requires you to physically open up your desktop computer and install the card in the slot inside your computer. The PCI serial port card can only be installed in desktop computers.
