Re: ROM Dump of Amiga Keyboard controller

From: Jim Brain <brain_at_jbrain.com>
Date: Sun, 20 Jul 2014 01:02:13 -0500
Message-ID: <53CB5B65.1090400@jbrain.com>
On 7/19/2014 10:36 AM, silverdr@wfmh.org.pl wrote:
> But inside the "loader" code loop you have two additional toggles 
> between TEST and NORMAL mode with "extra cycle" inbetween. What was 
> this needed for? If I understand correctly - the 6500 should be able 
> to *store* to its RAM while running in TEST mode, shouldn't it? 
The extra cycle is the dummy cycle when the sta actually happens.  I 
took the TEST_OFF and TEST_ON out of the code, it stopped working.

I can't say for certain, but it would seem like only registers can be 
written when test mode is high.

That seems strange.

Jim


-- 
Jim Brain
brain@jbrain.com
www.jbrain.com


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Received on 2014-07-20 07:00:02

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