Summary: 4-port cards

[Raymond Nijssen]

gemini at geminix.in-berlin.de (Uwe Doering) writes:
>rcbarn at rw7.urc.tue.nl (Raymond Nijssen) writes:
>>bill at unixland.uucp (Bill Heiser) writes:
>>>In article <T74R12w163w at aegis.or.jp> davidg%aegis.or.jp at kyoto-u.ac.jp (Dave McLane) writes:
>>>>   You can buy NS16550AFNs from Altex Electronics.
>>>Careful here ...  I ordered *NS16550A* chips [...] 
>>
>>Be even more careful here! Only the AFN version offers a 16 byte FIFO.
>
>I disagree. I developed FAS for NS16550A chips, and have six of them on my
>own serial card. And obviously, FAS uses the 16 byte FIFOs. The `AF' version
>has a faster timing, but is functionally equivalent to the `A' version. The
>trailing `N' indicates the packaging technique used for this chip, in
>this case a plastic body in DIL form.

My warning reflected the warnings some 2 years ago that there were NS16550A's
around with broken FIFO's; it was stated repeatedly that not all bytes of the 
FIFO were ok, though I didn't experience this myself: I just got the AF(N)
version which works fine.

-Raymond

-- 
| Raymond X.T. Nijssen  | Eindhoven Univ. of Technology                       |
| raymond at es.ele.tue.nl | EH 7.13, PO 513, 5600 MB Eindhoven, The Netherlands |
| "Don't put that on the wall in a tax-payer supported museum!"  Pat Buchanan |