From 0d9ebb07c5f38db36e20f8090f4be4d3ac5e32f3 Mon Sep 17 00:00:00 2001 From: AJR Date: Sat, 25 Nov 2017 12:27:19 -0500 Subject: mc68681: Another note (nw) --- src/devices/machine/mc68681.cpp | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/src/devices/machine/mc68681.cpp b/src/devices/machine/mc68681.cpp index 5b5d67aca92..f288a76971c 100644 --- a/src/devices/machine/mc68681.cpp +++ b/src/devices/machine/mc68681.cpp @@ -17,6 +17,10 @@ generates a 68000-compatible DTACK signal, instead of using generic RD and WR strobes as the 2681 does. The 68681 also adds a programmable interrupt vector, with an IACK input replacing IP6. + + The command register addresses should never be read from. Doing so may place + the baud rate generator into a test mode which drives the parallel outputs with + internal counters and causes serial ports to operate at uncontrollable rates. */ #include "emu.h" -- cgit v1.2.3