Path: utzoo!attcan!uunet!aplcen!haven!adm!smoke!gwyn
From: gwyn@smoke.BRL.MIL (Doug Gwyn)
Newsgroups: comp.sys.apple2
Subject: Re: Apple IIe Modem Problem
Message-ID: <13916@smoke.BRL.MIL>
Date: 20 Sep 90 21:46:50 GMT
References: <4526@crash.cts.com>
Organization: U.S. Army Ballistic Research Laboratory, APG, MD.
Lines: 11

In article <4526@crash.cts.com> tomk@pro-sol.cts.com (Tom Kelly) writes:
>It seems that if you turn interupts on and you software issues a control S
>when its copy buffer gets full, that the host should wait while the copy
>buffer is written to "disk" no matter what kind of disk it is.   After it has
>been written out , the buffer is cleared and the software issues a control Q
>and the host should resume sending.  That way nothing should ever be "lost".

In full-duplex operation, several more characters may arrive AFTER you
think you have sent the DC3 (^S) to block the transmitting system.  If
interrupts are off and frequent polling of the UART is not being done,
some of these incoming characters can indeed be lost.