INT 14H

[Paul Edwards]

Hi.

INT 14H is designed to read/write to a serial port.

I would like my software (OS) that uses this interface
to, on a machine that doesn't have a serial port, be
directed to some other device, like bluetooth to my
phone or Wifi to my router.

Is this possible?

Thanks. Paul.

[Peter Stuge]

Hi Paul,

Paul Edwards wrote:
> INT 14H is designed to read/write to a serial port.
>
> I would like my software (OS) that uses this interface
> to, on a machine that doesn't have a serial port, be
> directed to some other device, like bluetooth to my
> phone or Wifi to my router.
>
> Is this possible?

Sure. Implement a driver for that redirection which behaves as an
int14h handler and place the address of its entry point at address
0000:0080. (14h*4)

I'd suggest to save the original int14h entry point address into your
code and first call into that e.g. when queried by int14h users,
appending your fake serial port to the results.

If suitable for your hardware you could do all of it in an option ROM.

The method works with any BIOS.

//Peter