24 lines
688 B
Markdown
24 lines
688 B
Markdown
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# ATmega328 Interface Unit
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This MCU acts as a serial to I2C translator for the host
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computer. The serial protocol implements two
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interfaces. One for read requests and another for write commands.
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The data format of the write commands is given
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in the ATtiny85 I2C protocol document.
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Read requests return blocks of memory begining with the address
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specified in the last 'Set read address' command.
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## Read: Channel to Host
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Read a `<count>` bytes from a channel beginning at offset = 'offset'
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'r' <i2c-addr> <offset> <count>
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## Write: Host to Channel
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Write `<count>` bytes from from the host to a channel
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'w' <i2c-addr> <register> <count> <value-0> <value-1> ... <value-n>
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