Re: Detect a C128 from C64 mode

From: silverdr_at_wfmh.org.pl
Date: Thu, 23 May 2013 17:52:54 +0200
Message-Id: <8228DEC1-F7EB-4153-B911-7642D4815D1D@wfmh.org.pl>
On 2013-05-23, at 16:17, Greg King wrote:

>> Unfortunately, I don't think any of these work; they all set
>> the test-mode bit (bit 1) to 1 (on)?
> 
> Does that matter?  The original test bit (in $d016) crashed the system because it disabled the dynamic RAM refresh (therefore, it was removed).

That was actually the question from my original post: what does the "test bit" aka "test mode" does to the machine?

>  But, the new test bit doesn't do that -- and, the change is momentary. 

What do you mean? If bit 2 can't hold the "cleared" state, then with ror $d030 the "set" state will be shifted to bit 1. Meaning: no matter what was the state of bit 1 before the action - after the test, this bit will be set, right?

-- 
SD!
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Received on 2013-05-23 16:01:09

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