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All LCDs require refresh. On the character displays, this is usually hidden from you - you're not connecting directly to the LCD segments, there will be a driver chip intermediating. This can remember what the segments are supposed to be, because it's a relatively small amount of data. By comparison the high resolution graphics displays would require much ...

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https://en.m.wikipedia.org/wiki/LED-backlit_LCD LCD transmissive displays are either diffused edge-lit or back lit. The edge lit are spot LEDs on 1 or 2 sides constrained into the edge of the glass by U metal brackets with diffusion plastic layers between glass and crystal layer to spread the backlight evenly. For large LCD screens they use large diffused ...

3

An LCD doesn't emit light. It either has a reflector behind it, or a separate light source (backlight). The backlight may be controllable on any scale from a monolithic whole to a pixel. The LCD selectively blocks light. In a color LCD, each pixel will have 3 segments which correspond to red, blue, and green filters. Color is achieved by blocking these ...

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After getting this working on an MSP430 using nearly identical code, and staring hard at the oscilloscope, I realized that the SPI peripheral of the STM32 was performing 'data packing' on my bytes, resulting in 16 cycles per transfer rather than 8. I resolved the issue by using this method of setting SPI2->DR. *((uint8_t *)&SPI2->DR) = (uint8_t)...

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first of all you disable the CS before the transmition is over. while (!(SPI2->SR & SPI_SR_TXE)); will not work. You need to wait for TC flag before disabling the CS. This is one of the most common mistakes

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For a planar MOSFET like this the designation of the source and drain is not determined by the physical layout of the transistor...the layout is symmetric. If it is an NMOS then at any given instant the terminal with the lower voltage is the source and the terminal with the higher voltage is the drain. So, $V_{GS}$ has a consistent meaning regardless of ...

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Most graphics libraries use a frame buffer, and copy this to the LCD in one go. Preferably with DMA. This frame buffer keeps one full frame in memory. The advantage is quick rendering, and glitch free updates. The drawback is a large memory footprint. The ILI9486L only has one frame memory, and you can only directly read/write on this memory. The LCD is ...

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