Re: ibm750

[<jokim@jarthur.cs.hmc.edu>]

Thanks for the answer.  I'm forwarding this to the TP750 mailing list
since a couple folks are really mad at IBM that their $3000 machine has
a 16450.  It makes sense if it's a 486SL limitation.

In article <19940721.164333.8@almaden.ibm.com> writes:
>In <30mbrq$ij@jaws.cs.hmc.edu> John H. Kim writes:
>
>>The TP750's built-in serial port emulates a 16450 (you'd think in a
>>machine that costs $3000+ they'd pitch in the extra $10 for a 16550).
>
>Notebook computers generally don't have a separate UART.  (No room for
>one.)  The UART is emulated within one of the support chips.  Since
>the ThinkPad 750 has an Intel 486SL, it uses the Intel SL chipset, and
>that chipset emulates the 16450.  Probably all Intel 486SL notebooks
>have this restriction since they probably all use the same Intel SL
>chipset.
>
>If it's any consolation, the 755 and 360 use a newer chipset that does
>emulate the 16550.
>
>...Michael Graff


-- 
John H. Kim              | (This space to be filled when I think of
jokim@jarthur.cs.hmc.edu | something clever to use as a disclaimer)