16750 UART And here's another pinout: The 16750 is nearly identical to the 16550, but only available in PLCC-44 and SQFP-64 housings. I checked it with a TI datasheet. Some of the pins have different names compared to the 16550, in those cases I set the names according to TI's datasheet. By the way: Do you want to set links to the original manufacturer's web sites for datasheet download? For example: TI's 16750 page is at http://www-s.ti.com/cgi-bin/sc/device1.cgi?device=TL16C750&return=UARTS&des=ACE+(64-BYTE+FIFOS,+AUTO+F LOW+CONTROL,+LOW-POWER+MODES)&type=2 OK, here's my version of the 16750: 16750 Asynchronous serial interface controller (UART) with DMA support, automatic hardware flow control and 64-byte FIFOs. PLCC44 +---------------------------------------------------------------+ | 7 D5 | 18 XIN | 29 A2 | 40 /CTS | | 8 D6 | 19 XOUT | 30 A1 | 41 /DSR | | 9 D7 | 20 /WR1 | 31 A0 | 42 /DCD | | 10 RCLK | 21 WR2 | 32 /RXRDY | 43 /RI | | 11 SIN | 22 GND | 33 INTRPT | 44 VCC | | 12 | 23 | 34 | 1 | | 13 SOUT | 24 /RD1 | 35 /OUT2 | 2 D0 | | 14 CS0 | 25 RD2 | 36 /RTS | 3 D1 | | 15 CS1 | 26 DDIS | 37 /DTR | 4 D2 | | 16 /CS2 | 27 /TXRDY | 38 /OUT1 | 5 D3 | | 17 /BAUDOUT | 28 /ADS | 39 MR | 6 D4 | +---------------------------------------------------------------+ Bye, Martin Schmidt