Background information: The UART is the central element of any serial interface card. The use of UARTs without integrated FIFO buffer at the high baud rates needed for example in modern modems for proper function will result in extreme loads on the CPU: each received or send character generates an interrupt. The buffer integrated into the UART allows sending and receipt of multiple characters before an interrupt follows. Since the processor is interrupted less often, it is more efficient. In practice this means that the port has a significantly higher data throughput. This is particularly critical in the case of fast modems and ISDN connections.
Technical data:
Number of ports:
2 galvanically isolated RS232 ports
UART:
16550 with FIFO
Base addresses:
03F8H, 02F8H, 03E8H, 02E8H
Interrupts:
IRQ 3..7, IRQ 9..12
Baud rate:
50..115,200 baud
Data format:
any format
Signal lines:
RxD,TxD,RTS,CTS,DSR,DCD,DTR,RI
RS232 adapter
9-pole SUB-D plug
Galvanic isolation:
Isolation voltage min. 1 KV DC between PC and serial ports
