[ltp] TP 240 gets real modem support?

Eric Bentley linux-thinkpad@www.bm-soft.com
Sat, 29 Jan 2000 13:43:15


>One of the recent BIOS releases mentions:
>
>- (New) Setting for "Modem for Legacy OS" is added in Advanced Setup
>  menu of IBM BIOS Setup Utility
>
>Is that what I think it is? A "real" modem interface that doesn't
>require a driver? Anyone have more info on this?
>
>Unfortunately, my non-Linuxed sister is the one with the 240; I have
>the 600X. Any news on this for the rest of us?
>

On the earlier models of Thinkpads, (I believe the 380 and 390 models) this was
 used so that there was a second IRQ associated with a UART on the modem.  The
 UART was not a physical one but the signals could be made to look like one with
 the modem driver loaded.  So even though you have the UART address and IRQ, you
 still need the driver to operate them.  But legacy software could used the
 modem through this UART interface.   This is how the OS/2 driver I wrote works.
  I believe they have DOS support the same way but I did not write that so I do
 not know for sure.

Windows uses the COM interface so software does not need direct access to the
 I/O ports and therefore does not need this UART IRQ.  

-Eric


----- The Linux ThinkPad mailing list -----
The linux-thinkpad mailing list home page is at:
http://www.bm-soft.com/~bm/tp_mailing.html