ms-dos program com port not ready

[roberto]

My MS-DOS program writes to COM1 (it sends a short string
for opening a cash drawer attached to COM1). When run in
Windows XP, it always responds 'not ready'. A technical
colleague investigated and says that both DTR and CTS
lines are reported to an MS-DOS program running under
Windows XP as "low" even when they are "high". My MS-DOS
program is from a third party, so there is no way I can
alter it (eg to have not bother checking the COM1 port
status before sending the Open string). How can I get
this program to work properly in Windows XP?

 

[NobodyMan]

My MS-DOS program writes to COM1 (it sends a short string
for opening a cash drawer attached to COM1). When run in
Windows XP, it always responds 'not ready'. A technical
colleague investigated and says that both DTR and CTS
lines are reported to an MS-DOS program running under
Windows XP as "low" even when they are "high". My MS-DOS
program is from a third party, so there is no way I can
alter it (eg to have not bother checking the COM1 port
status before sending the Open string). How can I get
this program to work properly in Windows XP?

You may not get it to run in XP. Remember that XP was not built on
top of DOS, and doesn't contain DOS in any way, shape or form.

If your software is trying to access the COM port directly, you are
going to have a problem. That is a no-no in XP and your software
won't function properly.

Again, the software you are asking about may never work in XP. If
that's the case, you'll have to live with that fact and move on.