Comm and Width

[Mel Bishop]

Aldo's post got me curious so I finally found an old x486 running
pure dos 6.2 with a modem in it. Wrote the following test code:

        $lib all off
        $lib com on
        color 14,1
        cls

        a$ = string$(80,"A")

	width "com2:",10
rem	open  "com2:1200,n,8,1,rs,cs,ds,cd" for output as #1
rem	open  "com2:1200,n,8,1,rs,cs,ds,cd" for append as #1
rem	open  "com2:1200,n,8,1,rs,cs,ds,cd" for random as #1
	open  "com2:1200,n,8,1" for output as #1
        width "com2:",10

        delay 1
        print #1,"atz"
        delay 5
'-----------
	for x = 1 to len(a$)
	print #1,mid$(a$,x,1);
rem	print #1,mid$(a$,x,1)
	next x

rem	print #1,a$;
rem	print #1,a$
'-----------
        do until inkey$ <> ""

        if not eof(1) then
        t$ = input$(1,#1)
        print;t$;using$("### ",asc(t$));
        end if

        loop
        close #1
        end

Tried every possible combination. The un-rem'd lines that didn't
error out did not produce the desired results. i.e., no Cr's
every 10th character.

What are we missing?


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[This message has been edited by Mel Bishop (edited September 11, 2003).]

[Tom Hanlin]

WIDTH works on "a device opened for output". Your OPEN is for RANDOM access.


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Tom Hanlin
PowerBASIC Staff

[Aldo Cavini]

Mel,

I tried also what you suggested. Nothing changed - no CRs added. Is it possible it depends on the BIOS or the OS?

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[Mel Bishop]

Okay. Sorry you saw my original post. It was knee jerk which
shouldn't have happened.

I haven't tried this but you may want to:

width "com1:",10
open "com1:.....

i.e., set the width then open the port.
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[This message has been edited by Mel Bishop (edited September 11, 2003).]

[Aldo Cavini]

mel, i first replied too fast...

the reason i open the port, close and repoen is because it is not clear if the width statement works after the port has opened. from the printed manual:

if the device has already been opened, its width setting is not changed...

the trick to open, close and reopen is derived from the sample by matthias kuhn, at http://www.powerbasic.com/support/pb...read.php?t=789

aldo

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[this message has been edited by aldo cavini (edited september 11, 2003).]

[Mel Bishop]

Don't think my original response was accurate.


[This message has been edited by Mel Bishop (edited September 11, 2003).]

[Aldo Cavini]

I have some communication problems (may be I'll post something later...). I started considering the WIDTH statement, and found I don't understand it!

My communication problem is on a device which doesn't need CRs or LFs to be automatically inserted at all. I never used a statement like WIDTH "COM1:", 255 to disable the automatic CR insertion, as I never suspected it was needed.

This moment I'm trying the WIDTH statement. I connected toghether the TX and RX lines and run the following code:

open "com1:4800,n,8,1,cs,rs,ds,cd" as #1
width "com1:", 10
close #1
open "com1:4800,n,8,1,cs,rs,ds,cd" as #1
width "com1:", 10
 
do while inkey$ = ""
 
  print #1, "123456789012345678901234567890";
  t = timer
  do while timer - t < 1
    if loc( 1 ) then
      print asc( input$( 1, 1 ) );
    end if
  loop
  print
loop

The result is every second I back receive the 30 chars I print, but I never see the CR chars I expected. I tried also to simply open the COMM port without WIDTH statements: I expected to see a CR every 80 Tx chars, but it doesn't happen.

The question is: is WIDTH needed to avoid the CRs insertion on printing to a communication port?

Aldo


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