LCD Controller (What's the meaning of 16 bits per pixel?)

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Hi,

I'm looking to interface the AT32AP7000 with a TFT LCD.. Looking at the datasheet under LCDC, I see that I can interface a TFT with "1, 2, 4 or 8 Bits per Pixel (Palletized), 16 or 24 Bits per Pixel (Non-palletized)"

However, the lcd I wish to interface is 6 bits per color which I would take as 18 bits per pixel..

Later in the datasheet in the section labeled "35.12.2 TFT Mode Example", there are example settings for an NEC panel w/ model# NL6448BC20-08.. The AT32AP7000 datasheet refers to the NEC panel as "16-bit single scan" yet the datasheet for the NEC panel shows "6 bit digital signals for data of RGB colors" which I would interpret as 18 bits per pixel just like my panel (http://www.arcom.com/products/icp/dev_kits/NEC_TFT_Nov06.pdf)..

I'm obviously reading this wrong.. Can someone explain what is meant by "16 bits per pixel" in the Atmel datasheet and how this corresponds with "6 bits per color" on the NEC panel?

Thanks

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fabuser wrote:
I'm looking to interface the AT32AP7000 with a TFT LCD.. Looking at the datasheet under LCDC, I see that I can interface a TFT with "1, 2, 4 or 8 Bits per Pixel (Palletized), 16 or 24 Bits per Pixel (Non-palletized)"

18-bit is not on the list of supported video modes. 16-bit (5:5:5 + intensity) can be used on these panels, it's just that the intensity bit runs the LSB of _all_ colours. See the last column of table 35-12 (page 818) of revision I of the AP7000 data sheet for how to hook up this type of panel. Note that the 3 intensity bits are in fact the same signal, just duplicated for convenience and should be hooked to the LSB of each colour. Each further bit should be then shifted down, that is, green0 on the lcd goes to intensity, green1 on the lcd goes to green0 on the ap7000 etc.

-S.