Re: C128 memory - B series compatibility - Basic using 256k - a new version of the hardware for 256k

From: Jim Brain <brain_at_jbrain.com>
Date: Mon, 7 May 2018 13:31:03 -0500
Message-ID: <942c7eee-3780-49a6-7953-aa4946d01236@jbrain.com>
On 5/7/2018 12:01 PM, smf wrote:
> On 07/05/2018 14:42, Mia Magnusson wrote:
>> But since you can relocate zero page and the stack page independent of
>> all other switching you don't need to care about "pulling away the
>> floor you are standing on".
>
> It's not just that, the preconfiguration registers would be kinda 
> broken if they didn't have their own copy of the extra bits.
>
>
>
How does one get a handle on how the MMU works? I am looking at:


https://patpend.net/technical/c128/C128io.doc.txt

http://www.oxyron.de/html/registers_mmu.html

https://ia801002.us.archive.org/10/items/Compute_s_Mapping_the_Commodore_128/Compute_s_Mapping_the_Commodore_128.pdf

I see the registers, but I'm not sure I understand the PCR and LCR 
regs.  Is there a document that explains these?

Jim


-- 
Jim Brain
brain@jbrain.com
www.jbrain.com
Received on 2018-05-07 21:00:03

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