User guide

SFSU - Embedded Systems Tutorial Nano- Electronics & Computing Research Lab
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LINE, DROP LCD, HOLD, DISPLAY ON, and MODE SET AND PRINT STRING. These
reset needs to be done three time to because we need to initialize enable to high and register
select and read/write to low signals. These steps are also done to communicate with the LCD to
determine if it will be an 8 or 4 bit data bus, this is done by setting the data bus equal to the hex
value eight(8’h38). Before we can write to the screen we need to clear the LCD display, this is
done by changing the data bus equal to 8’h01 (Start of heading). Finally when we need to display
the screen we set enable and read/write to high and reset to low, this is done because this allows
us to write data to the LCD. In the print string case statement we added an else if (index ==line1)
because without this the LCD wouldn’t know when the next line begin or the first line starts.