Re: Quick COMM question

 BBS: Inland Empire Archive
Date: 01-31-93 (07:41)             Number: 363
From: DICK DENNISON                Refer#: NONE
  To: SCOTT DRYSDALE                Recvd: NO  
Subj: Re: Quick COMM question        Conf: (2) Quik_Bas
 DD>   The break signal is NO signal, ie., the absense of a signal for 1 BLK
 DD> of modulated time.  (I don't have a solution).

SD> Oh.  Sounds tough.  Would it be possible to close the com port send an
SD> boost back the dtr before reopening, and during that little bit of tim
SD> have a break?   Maybe this is one of the things you have to go to anot
SD> language for though...  I certainly don't know, but if the answer come
SD> chances are I'll be saving it on disk...

'This is untested, but I think it should work:

'Dick Dennison 1:272/34  1/93 PubDomain
Port$ = "COM4:"
    CASE "COM1:"
            BaseAddress% = &H3F8
    CASE "COM2:"
            BaseAddress% = &H2F8
    CASE "COM3:"
            BaseAddress% = &H3E8
    CASE "COM4:"
            BaseAddress% = &H2E8

OldLCR% = INP(BaseAddress% + 3)  'Get line control register
OUT (BaseAddress% + 3), (OldLCR% OR 128)  'Turn on break
SLEEP 1  'Not sure if needed              'Pause a sec
OUT (BaseAddress% + 3), (OldLCR% AND NOT 128) 'Turn off break
OUT (BaseAddress% + 3), OldLCR%  'Restore Line Control Reg

--- VP [DOS] V4.09e
 * Origin: The MailMan  (914)374-3903 NY Quick Share Pt #7 *HST (1:272/34)
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