Error: "Cannot set serial info:Address already in use&q

[Quasar]

Hey all, I purchased a 4-port PCi serial expansion card and I was trying to configure it. The process is supposed to be straight forward but I'm facing some problems. According to the installation manual, I'm supposed to use "more /proc/pci" to get the I/O port address of the card, I did that and was able to obtain two addresses, then I'm supposed to use the following command to assign the serial ports of the card to ttySx: "setserial /dev/ttySx port [address] irq [irq] UART16550A Baud_base 921600". My motherboard has only one serial port, which means that I'll be using ttyS0 to ttyS4. The problem is that when I use this command, I get the error "Cannot set serial info:Address already in use", and sometimes I get "LSR Safety Check Engaged!". While Puppy is booting, I noticed the ttySx being set correctly by the operating system but when it finishes booting and I check the ports with "setserial /dev/ttySx -a" I get an unknown UART which means it's not set correctly. This problem is only with the card's ports, the motherboard's serial port works just fine. How could I find out if the address is already assigned or being used and what can I do to solve this problem?

P.S. I'm using Puppy 1.0.5