31 lines
1.2 KiB
Markdown
31 lines
1.2 KiB
Markdown
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Tutorial 5b - indicator LED on IOE
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==================================
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This tutorial will show you how to add LEDs to an I/O expander.
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It is assumed the reader is familiar with LEDs from tutorial_5a_LED_on_uC.md
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and familiar with I/O expanders from tutorial_4c_split_keyboard_with_IOE.md.
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Adding LEDs to the basic breadboard keyboard
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The breadboard keyboard modifies the basic breadboard keyboard described in [tutorial_1_breadboard_keyboard.md](tutorial_1_breadboard_keyboard.md)
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Add components to the breadboard as shown in the picture.
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The two clear plastic cylinders are red and yellow LEDs.
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Each LED is in series with a 4.7k Ohm current limiting resistor.
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LED anodes (the longer lead) are powered by pins GPA6 and GPB6.
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LED cathodes (the shorter lead) are connected to a grounded terminal strip.
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keybrd sketch with LEDs on IOE
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------------------------------
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The [keybrd_5b_LED_on_IOE.ino](keybrd_5b_LED_on_IOE/keybrd_5b_LED_on_IOE.ino) sketch will run on the above breadboard keyboard.
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The sketch features:
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* multiple layers
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* split keyboard
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* LED on controller
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* LED on IOE write port
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* LED on IOE read port
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