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@ -279,6 +279,15 @@ The `SPI_CTRL` register at `0x00DF1F` is used to control the SPI subsystem:
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- Bit 2 controls the "auto-transmit" function, which begins reading a new byte from SPI (sending the value `0xFF`) automatically when the `SPI_DATA` register is read. This can be used to simplify and speed up SPI reads.
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- Bit 2 controls the "auto-transmit" function, which begins reading a new byte from SPI (sending the value `0xFF`) automatically when the `SPI_DATA` register is read. This can be used to simplify and speed up SPI reads.
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- Bit 7 will read as a `1` value as long as a byte is being transferred over SPI.
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- Bit 7 will read as a `1` value as long as a byte is being transferred over SPI.
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## Colour Palette
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VERA supports a single, shared palette of 256 colours, each of which is freely chosen from among the 4,096 possible colours the hardware can generate.
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The palette is stored in VERA memory beginning at VERA address `0x1FA00`, and consists of 256 entries with the following format:
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| Byte | Bit 7 | Bit 6 | Bit 5 | Bit 4 | Bit 3 | Bit 2 | Bit 1 | Bit 0 |
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| :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: | :---: |
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## 16-Bit Reads/Writes
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## 16-Bit Reads/Writes
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With appropriate configuration of registers, it is possible to perform sequential 16-bit reads and writes to VERA address space:
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With appropriate configuration of registers, it is possible to perform sequential 16-bit reads and writes to VERA address space:
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