Here is a 1996 I/O card which adds two serial ports to any PC with a 16-bit ISA slot.
There are sockets for both UARTS, so the large 16450 chips can be upgraded to 16550 UARTS if necessary. 8-bit I/O cards rarely offered enough IRQs for a system that requires a third serial port and a parallel port. It was quite common for a multimedia PC from 30 years ago to run out of IRQs. This card allows you to configure each serial port from among the following IRQs: 3, 2/9, 4, 5, 6, 7, 10, 11, 12, 14, or 15
Jumper settings can be found at this will receive the exact item pictured here.
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