26 lines
1.2 KiB
TeX
26 lines
1.2 KiB
TeX
To illustrate how the components work together and can be used in various
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different applications, a small text-adventure with audio effects was written in
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C. The main goal was to show the capabilities of even small systems like the
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one developed.
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\subsection{General Implementation details}
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Like the before examples, the textadventure was implemented on an ATMega2560
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and uses 3 different Registers for transmission: PORTF, PORTK and PORTL for
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address bus, data bus and control bus respectively, as can be seen in listing
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\ref{lst:textadv-avr.h}
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\lstinputlisting[language=C,frame=trBL,
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breaklines=true, breakautoindent=true, formfeed=\newpage,
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label={lst:textadv-avr.h}, caption={The avr.h header file},
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columns=flexible, style=cstyle]{./code/textadv/include/avr.h}
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The in listing \ref{lst:textadv-avr.h} shown defines MR_SHIFT, WR_SHIFT,
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RD_SHIFT, CS_UART_SHIFT and CS_DAC_SHIFT are used to indicate the position of
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the corresponding control lines inside the control bus register. All other
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shift values are the same bitordering in input as in output.
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The BUS_HOLD_US is used to tell the avr how many microsecons it takes for the
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data bus to be latched into input register of the devices on write or how long
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it takes for the data bus to become stable on read.
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