[alt.msdos.programmer] HELP!!!!!!

DGH103@PSUVM.BITNET (12/12/89)

Ok, I don't think that I explained myself very well the last time I posted this
message. I will try to explain it better this time. I have a Tandy 1400LT and
for some reason they have the modem and the com port attached together,
consequently I cannot use the modem and the mouse at the same time, but that's
not the problem. What I want to do is write a program that I will run when I am
going to use ProComm that will switch from the com port to the modem. I have
the service manual for the 1400 and I am a little lost. I will show how thw pag
e looks:
                          I/O Address Map
System Status Register

    Address         Bit      Contents                      Control

(Write Register)
    0FCH             2       Modem/RS-232C Switch        1/Modem,0/RS-232C

I guess I should explain that to switch between them now I have to use the
CTRL-ALT-INS key sequence to get to a setup menu then switch to the one I want.

Can anyone help me? Any help would really be appreciated!!

-------
*************************************************************************
* Darryl G. Hickson                  Penn State University              *
* 761 Stratford Drive                DGH103@PSUVM.BITNET                *
* State College, PA 16801                                               *
* (814) 867-2234                                                        *
*************************************************************************

jmv@sppy00.UUCP (Jim Vickroy) (12/13/89)

In article <89346.001555DGH103@PSUVM.BITNET> DGH103@PSUVM.BITNET writes:
=>not the problem. What I want to do is write a program that I will run when I am
=>going to use ProComm that will switch from the com port to the modem. I have

=>                          I/O Address Map
=>System Status Register
=>
=>    Address         Bit      Contents                      Control
=>
=>(Write Register)
=>    0FCH             2       Modem/RS-232C Switch        1/Modem,0/RS-232C
=>
=>Can anyone help me? Any help would really be appreciated!!
=>

From the "man" page you included above it looks like you need to tweek 
port 0FCH to switch to either the modem or the RS232 port. Try this:

    ;
    ; Switch to modem
    ;
    IN	    AL,0FCH
    OR	    AL,02H
    OUT	    0FCH,AL
    
    ;
    ; Switch to RS232
    ;
    IN	    AL,0FCH
    AND	    AL,0FDH
    OUT	    0FCH,AL

Now you'll have to build the rest of the logic around these segments. The
same could easily be done in 'C'.

jim
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:::: ::: ::  ::   :    :   Jim Vickroy
|OC| ||| ||  ||   |    |   Telecommunications Systems Engineering
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:::: ::: ::  ::   :    :   Dublin, Ohio
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JGROVER@MAINE.BITNET (John Grover) (12/16/89)

I think Jim Vickroy is on the right track except the register is
write only -- so we need to find a way to read the current status
before writing to the register. Otherwise, we don't know what value
to write to the register.

John Grover
University of Maine Computing Center