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ARA Video Digitizer

162 bytes added, 13:29, 8 May 2010
/* Technical */
The hardware consists of an A/D converter, and bunch of logic chips. It does also includes two 8K SRAM chips, used as 16K capture buffer (the image is captured to that buffer in realtime, and can then be read by software at slower speed).
The device connects to SCART connector on TV Set (or Video Recorder (or camcorder or other picture source). There seem to be no attempts to decode SECAM color informations, ie. only luminance (brightness) seems to be supported. Luminance should be same in all countries, so it should also work with PAL/NTSC.
Two capture formats are supported: 320x200x4 and 160x200x16. Of which, in practice, the software supports only max 8 colors, not 16 colors (nethertheless, the actual hardware might, or might not support 16 colors, and it's just the software ignoring their LSBs; the CPC's 27-color palette isn't suitable for displaying 16 "grayscales").
 
The captured data bytes are having the bits arranged differently as CPC's VRAM. For details, see the mode 0 and mode 1 translation tables in the disassembly.
=== I/O Port Summary ===
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