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Speccy Port

1,062 bytes added, 13:12, 1 October 2012
/* Real-Time Conversion of Spectrum graphics */
Advantages:
* Pixel data took less RAM compared to storing it in Amstrad's mode 1 form, so could run on a 64K Ram machine (CPC464 and CPC664).
 
==Mode1 and screen dimensions==
 
Amstrad's mode 1 is the closest mode which compares with the Spectrum's graphical abilities.
 
The pixels are almost the same size. The CPCs screen dimensions can be reprogrammed to re-create the Spectrum's 256x192 resolution.
 
However, the CPC has a different "pixel clock" compared to the Spectrum. The CPC was designed for a 320x200 display instead of a 256x192 display and in fact the the pixels are smaller on the screen when you compare mode 1 (the closest equivalent on the CPC) to the Spectrum.
 
So when the screen is reprogrammed, you end up with a larger border on the CPC.
 
This (the larger border) led to the false argument that the CPC's resolution was inferior to the Spectrum one although the amount of pixels on the screen is EXACTLY the same.
 
There are advantages to reprogramming the screen dimension to match the Spectrum's.
* Graphics/levels would not need to be designed for a wider screen (320 compared to 256)
* For the Amstrad, a 320x200 screen normally takes 16K, but when reduced in size it takes 12K.
====Original consequences (under construction)====
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