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From: dca@toylnd.UUCP (David C. Albrecht)
Newsgroups: comp.sys.amiga.tech
Subject: Re: A Cost Effective MULTI-SERIAL Device Proposition
Message-ID: <307@toylnd.UUCP>
Date: 9 Feb 90 07:51:29 GMT
References: <76649@tut.cis.ohio-state.edu> <90037.161429NETOPRBH@NCSUVM.BITNET>
Distribution: usa, world
Lines: 16

In article <90037.161429NETOPRBH@NCSUVM.BITNET>, NETOPRBH@ncsuvm.ncsu.edu (Brandon Hill) writes:
> First, the game port cannot alone drive a serial connection, as it is not
> set up to sink or source the currents required for a serial connection.
> 
> Second, you can't directly receive RS-232 standard signals, because they
> can be anywhere between -12 and +12 volts (way out of line with what you
> can expect to apply directly to the game port)



Check out the MC1488 & MC1489 ICs (I think Radio Shack still carries them
as 276-2520 & 276-2521).  These chips are quad line drivers and receivers
respectively.  Their intention is DTL/TTL to RS232 conversion (or vice
versa).

David Albrecht