The INT14/AH81 function is not documented as a PC's serial port function. I haven't figured out yet what it is supposed to do.
Some thoughts of what it could be:
- Maybe your program comes with an own serial port driver that fails to load in DOSBox
- 81H works on the real PC because of some side effect
- 81H is an unocumented but working function on a real PC

The program doesnt have its own serial port drivers. I cannot get the radio and PC to communicate in Windows due to the speed of the PC. These radios are 15 years old it doesnt like the 3.0ghz PC 😀
I have the serial turned on in the BIOS, it shows up in the device manager as well. I've slowed the speed of the COM port as well. Any other suggestions to check?

This is a code problem, nothing that could be fixed by tinkering with settings.

ok

derrickwhitt wrote:

The program doesnt have its own serial port drivers.

However, it may very well rely on external 3rd party drivers. See here for example. It mentions COURIERS.COM, COMM-DRV and VIDEO FOSSIL as possible candidates.

JAL

FOSSIL was a serial port driver for BBS software wasn't it?

derrickwhitt wrote:

The program doesnt have its own serial port drivers. I cannot get the radio and PC to communicate in Windows due to the speed of the PC. These radios are 15 years old it doesnt like the 3.0ghz PC 😀
I have the serial turned on in the BIOS, it shows up in the device manager as well. I've slowed the speed of the COM port as well. Any other suggestions to check?

Do you have a copy of DOS laying around? Or can you download a freeDOS ISO image to test? Maybe it's Windows and not the speed of your CPU.

The last alternative of course is to buy an older PC. Even crappy slow laptops can be had on eBay for cheap. Or try MS VirtualPC with DOS. It supports serial ports too.

Or try MS VirtualPC with DOS. It supports serial ports too.

That won't get around the problem that you need some tsr/driver for it to work.

wd wrote:

Or try MS VirtualPC with DOS. It supports serial ports too.

That won't get around the problem that you need some tsr/driver for it to work.

Perhaps I don't understand the OP's original application, but I believe VPC just presents the mapped serial port like it was on the "box". I have run Qmodem from a DOS VirtualPC without problems.

As hal already said the standard serial interface doesn't provide the functions needed for this app.

Program seems to work on real hardware though...
( http://groups.yahoo.com/group/radio-programmi … g/message/48184 )

Ok i'll try to check if some bios can provide this, maybe even dos does that
(iirc dos only adds the hw stack stuff for those irqs though).

There is even an example program availible...

DirectSerial patch

I've yet to check some stuff, but it seems like

- 81H works on the real PC because of some side effect
- 81H is an unocumented but working function on a real PC

can be excluded.

After the unsupported INT 14/AH=81 call, the program goes on to do an AH=00 (initialize port) and AH=01 (write character to port) before displaying its error message. Perhaps it is looking for a driver or some such with function 81, but its behavior suggests that it does not rely upon finding something.

Now it depends if the app here behaves similar...

derrickwhitt: There has been a fix to the INT14 interface since 0.72, maybe try a DOSBox CVS build.

h-a-l-9000: I've just found DOSbox and want to use it for serial stuff, and would like to get the CVS build but can't find it. Can you give me a pointer?

Do you know what the changes to INT14 are since .72?

Thanks!

Brian1234 wrote:

h-a-l-9000: I've just found DOSbox and want to use it for serial stuff, and would like to get the CVS build but can't find it. Can you give me a pointer?

http://tinyurl.com/7f2nuj

MiniMax wrote:

http://tinyurl.com/7f2nuj

lol :)

JAL