Palette RAM: Difference between revisions

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[[File:Aes_palram.jpg|thumb|right|CXK5864 8KiB RAM chips as palette RAM in a AES system]]
[[File:Aes_palram.jpg|thumb|right|CXK5864 8KiB RAM chips as palette RAM in a AES system]]
[[File:CXK5864BSP-10L.jpg|thumb|right|CXK5864 8KiB RAM chips as palette RAM in a MV2F system]]
[[File:BR6265BF-10SL.jpg|thumb|right|BR6265BF 8KiB RAM chips as palette RAM in a MV1AX system]]
Palette RAM is 16KiB (2 banks of 256 palettes of 16, 16bit [[colors]]), it contains color data for each [[palettes|palette]].
Palette RAM is 16KiB (2 banks of 256 palettes of 16, 16bit [[colors]]), it contains color data for each [[palettes|palette]].


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=Speed=
=Speed=


Should be 100ns or less (2.5mclk).
Should be 120ns or less (3mclk).
 
The CXK5864BSP-10L is a 8192-word x 8-bit high speed CMOS static RAM.
 
The CXK5864BSP comes in 3 packages:
 
- CXK5864BSP-70L for 70ns (access time)
 
- CXK5864BSP-10L for 100ns (access time)
 
- CXK5864BSP-12L for 120ns (access time)


[[Category:Video system]]
[[Category:Video system]]
[[Category:Chips]]
[[Category:Chips]]

Latest revision as of 20:01, 29 April 2018

File:Aes palram.jpg
CXK5864 8KiB RAM chips as palette RAM in a AES system
CXK5864 8KiB RAM chips as palette RAM in a MV2F system
BR6265BF 8KiB RAM chips as palette RAM in a MV1AX system

Palette RAM is 16KiB (2 banks of 256 palettes of 16, 16bit colors), it contains color data for each palette.

It is accessible directly from the 68k memory space.

Speed

Should be 120ns or less (3mclk).

The CXK5864BSP-10L is a 8192-word x 8-bit high speed CMOS static RAM.

The CXK5864BSP comes in 3 packages:

- CXK5864BSP-70L for 70ns (access time)

- CXK5864BSP-10L for 100ns (access time)

- CXK5864BSP-12L for 120ns (access time)