On Sat, 23 Apr 2011 11:46:13 AM Yuhong Bao wrote:

> Enter these instructions using the A command and execute with the T
> command: mov AX, E801
> INT 15
> INT 3
>
> And provide the results of the AX, BX, CX, and DX registers after
> the INT 15h.

OK, so I'm a novice so I'll recap what I did.  Starting with FreeDOS
boot floppy and copied debug.com and debug98.com to the FreeDOS
directory on it.  Booted from the floppy, selected option 2 (safe 
mode, no drivers loaded).  Typed debug and then:

- A
2890:0100 mov AX, E801
2890:0103 int 15
2890:0105 int 3
2890:0106
- t
AX=E801 BX=0000 CX=0000 DX=0000 SP=FFFE BP=0000 SI=0000 DI=0000
DS=2890 ES=2890 SS=2890 CS=2890 IP=0103 NV UP DI PL NZ NA PO NC
2890:0103 CD15      INT      15
-

Does that look correct ?  I presume it was just <enter> to leave
the 'A' mode to go back to the command mode ?

cheers,
Chris
-- 
 Chris Samuel  :  http://www.csamuel.org/  :  Melbourne, VIC

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