BBS: Inland Empire Archive
Date: 04-10-92 (22:04) Number: 13
From: TRENT SHIRLEY Refer#: NONE
To: JIM TANNER Recvd: NO
Subj: Re: Exiting a door Conf: (2) Quik_Bas
Here is the patch as it was posted on this base before.
You should be able to follow the directions and patch the
files yourself. Alternatively, you can get a copy of the
BASWIZ library and use those com routines. They are
allready set to NOT drop carrier unless you say to. They
work very well.
************************************************************
******************
SUBJECT: 4.5 DTR patch
Microsoft's solution to 'fixing' the DTR drop problem with QB 4.5 when
closing the communications port by outputing a 3 to the modem status
register, is not a sound or reliable solution. Many modems simply respond
too quickly to the loss of DTR. The correct solution is to of course not
turn DTR off in the first place. However, after many years and many versions
of Quick Basic, it is apparent that Microsoft either does not listen to its
customers or they simply do not care. Sound programming practices dictate
that when you directly manipulate a hardware port, you restore that port to
the exact same conditions it had prior to your touching it. In the case of
DTR, this means that if DTR were ON when the QB program loaded, then DTR
should remain ON when the QB program ends. If DTR was OFF when the program
loaded, then fine, turn it OFF when the program ends. To the end that it is
an ongoing struggle to get Microsoft to listen to the needs of the
programmer, the following patches are provided to enable you to patch your
copies of BRUN45.EXE and BCOM45.LIB. Before beginning, make sure you have
backup copies of BRUN45.EXE and BCOM45.LIB.
BCOM45.LIB DTR Patch --------------------
With Debug in a DOS path, type :
debug bcom45.lib
Type :
s cs:0 ffff b0 00 e3 01
Debug should show :
xxxx:1529
where xxxx can be any number depending upon where Debug loaded the
program into memory. In any case, the number is not important.
Type :
u 1529
Debug should show :
MOV AL,00
JCXZ 152E
INC AX
ADD DX,+04
OUT DX,AL
This is where QB graciously resets the comm port to parameters it thinks
the comm port should have.
To fix the problem, Type :
a 1529
mov al,01
[Enter]
a 152d
nop
[Enter]
where [Enter] is the Enter key (do not type the characters)!
To verify that you typed everything correctly, Type
u 1529
Debug should show :
MOV AL,01
JCXZ 152E
NOP
ADD DX,+04
OUT DX,AL
To save the corrections Type :
w
Debug should show :
Writing 35EF7 bytes
Now type Q and you are finished patching BCOM45.LIB
BRUN45.EXE DTR Patch --------------------
First, rename BRUN45.EXE to BRUN45.X
With Debug in a DOS path, type :
debug BRUN45.X
Type :
s cs:0 ffff b0 00 e3 01
Debug should show :
xxxx:9E78
where xxxx can be any number depending upon where Debug loaded the
program into memory. In any case, the number is not important.
Type :
u 9e78
Debug should show :
MOV AL,00
JCXZ 9E7D
INC AX
ADD DX,+04
OUT DX,AL
This is where QB graciously resets the comm port to
parameters it thinks the comm port should have.
To fix the problem, Type :
a 9e78
mov al,01
[Enter]
a 9e7c
nop
[Enter]
where [Enter] is the Enter key (do not type the characters)!
To verify that you typed everything correctly, Type
u 9e78
Debug should show :
MOV AL,01
JCXZ 9E7D
NOP
ADD DX,+04
OUT DX,AL
To save the corrections Type :
w
Debug should show :
Writing 12E80 bytes
Now type Q and you are finished patching BRUN45.X
Rename BRUN45.X back to BRUN45.EXE
The ever powerful Code View debugger was used to to find these addresses
by tracing a QB program which had but two statments :
OPEN com port
CLOSE com port
************************************************************************
Hope that helps.
Later. Trent
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* Origin: The Owl's Domain (413) 582-1844 (1:321/118)
