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From: sellgren@snow.Berkeley.EDU (Steve Sellgren)
Newsgroups: comp.sys.mac.programmer
Subject: SCC and external clocking
Keywords: SCC
Message-ID: <40925@ucbvax.BERKELEY.EDU>
Date: 11 Feb 91 18:57:39 GMT
Sender: nobody@ucbvax.BERKELEY.EDU
Reply-To: sellgren@snow.Berkeley.EDU (Steve Sellgren)
Organization: Cal-Berkeley
Lines: 15


I'm trying to filter a/d samples through a mac II, coming in through
the modem port.  The problem is that I need a data rate faster than
the 57.6 Kbaud that Inside Mac says is the fastest.  Apparently AppleTalk
runs around 230Kbaud, but I hear that external clocking can push the SCC
to rates around 4Mbaud (not that an application could keep up with that).
Looking at the control codes that are passed to the ROM routines, it seemed
plausible that a baud rate of 0 might really be external clocking, but that
didn't work...

If someone could please clue me in on ways to do faster data transfer,
especially externally clocked, I'd really appreciate it.

Steve Sellgren
University of California, Berkeley