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ZX Spectrum +2A/2B, +3/3B

1,776 bytes added, 04:41, 19 November 2012
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==Timings and Contention==
The contention and ram timings on the +3 and Black +2 differ significantly from earlier models due to the redesigned [[The Amstrad ASIC|gate array]]. Timing patterns and memory contention are described in detail in the [[Contended_memory#.2B2A_.2F_.2B3|contended memory]] article.
 
==Paging==
The memory space is divided into four 16k pages and can be paged in two modes.
 
====Standard paging mode====
The 64k of ROM and 128k of RAM can be paged into the memory space as shown in the diagram below:
 
<!-- table of memory pages with style based on the wikitable class -->
{| style="text-align: center; border-collapse:collapse; margin: 1em 1em 1em 0;"
|- style="height: 5em; background: #f9f9f9;"
| style="width: 5em; background: #f2f2f2; font-style:italic; border: 1px #aaa solid;" | 0xFFFF <br />-<br />0xC000
| style="width: 5em; border: 1px #aaa solid;" | Bank 0
| style="width: 5em; border: 1px #aaa solid;" | Bank 1
| style="width: 5em; border: 1px #aaa solid;" | Bank 2
| style="width: 5em; border: 1px #aaa solid;" | Bank 3
| style="width: 5em; border: 1px #aaa solid;" | Bank 4
| style="width: 5em; border: 1px #aaa solid;" | Bank 5<br />(screen 0)
| style="width: 5em; border: 1px #aaa solid;" | Bank 6
| style="width: 5em; border: 1px #aaa solid;" | Bank 7 <br />(screen 1)
|- style="height: 5em; background: #f9f9f9;"
| style="width: 5em; background: #f2f2f2; font-style:italic; border: 1px #aaa solid;" | 0xBFFF <br />-<br />0x8000
| style="border: 1px #aaa solid;" | Bank 2
|- style="height: 5em; background: #f9f9f9;"
| style="width: 5em; background: #f2f2f2; font-style:italic; border: 1px #aaa solid;" | 0x7FFF <br />-<br />0x4000
| style="border: 1px #aaa solid;" | Bank 5
|- style="height: 5em; background: #f9f9f9;"
| style="width: 5em; background: #f2f2f2; font-style:italic; border: 1px #aaa solid;" | 0x3FFF <br />-<br />0x0000
| style="border: 1px #aaa solid;" | ROM 0
| style="border: 1px #aaa solid;" | ROM 1
| style="border: 1px #aaa solid;" | ROM 2
| style="border: 1px #aaa solid;" | ROM 3
|}
<!-- end of memory map -->

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