Accessing COM3/4:

 BBS: Inland Empire Archive
Date: 12-02-92 (08:21)             Number: 336
From: PETER BARNEY                 Refer#: NONE
  To: SCOTT WUNSCH                  Recvd: NO  
Subj: Accessing COM3/4:              Conf: (2) Quik_Bas
 >   I seems to me that I've seen a post here about COM3/4.  All that
 > was done was simply switch the addresses in low memory, and then 3
 > & 4 became 1 & 2. ;) Does anybody still have this?  Or at least have
 > the PEEK/POKE addresses necessary?

DEF SEG=0
'swap com1 & 2 with com3 & 4
DEF SEG = &H40

a1 = PEEK(0) 'com1
a2 = PEEK(1)
a3 = PEEK(2) 'com2
a4 = PEEK(3)

POKE 0, PEEK(4)
POKE 1, PEEK(5)
POKE 2, PEEK(6)
POKE 3, PEEK(7)
POKE 4, a1
POKE 5, a2
POKE 6, a3
POKE 7, a4
DEF SEG

Call it at the beginning of the program and then again at
the end to "re-swap" them back

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