34 lines
1.0 KiB
Arduino
34 lines
1.0 KiB
Arduino
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/* unit test for Port_MCP23018
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Picture of hardware is in unit_tests/PortMCP23018_read/PortMCP23018_bb.JPG todo
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The setup is an MCP23018 I/O expander on a Teensy LC controller.
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MCP23018 port-A GPIO pins are not connected to anything.
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Port-A GPIO-pin ouputs alternate between 0 and 3.3 volts.
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volt meter between pin A1 and power because
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MCP23018 has open-drain outputs (open-drain can only sink current)
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Use a volt meter to measure port-A GPIO-pin outputs or red LED.
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*/
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#include "Port_MCP23018.h"
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const uint8_t IOE_ADDR = 0x20; //MCP23018 address ADDR pin grounded
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Port_MCP23018 portA(IOE_ADDR, 0, 0);
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void setup()
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{
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delay(6000);
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Keyboard.println("PortMCP23018_write.ino");
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portA.beginProtocol();
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portA.begin(LOW); //HIGH or LOW, not matter if readPins=0
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}
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void loop()
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{
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portA.write(~0, HIGH); //set all GPIOA pins HIGH
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Keyboard.print("+");
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delay(2000);
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portA.write(~0, LOW); //set all GPIOA pins LOW
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Keyboard.print("0");
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delay(2000);
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}
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