37 lines
1.1 KiB
C++
37 lines
1.1 KiB
C++
/* unit test for PortWrite_MCP23S17
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Picture of hardware is in unit_tests/PortRead_MCP23S17/PortRead_MCP23S17_bb.JPG
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The setup is an MCP23S17 I/O expander on a Teensy LC controller.
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MCP23S17 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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Use a volt meter to measure port-A GPIO-pin outputs.
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MCP23S17 on 3.3v does not output enough power to reliable light LEDs
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LED lights w/o resistor
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LED not light with 56 ohm resistor
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*/
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#include "PortIOE.h"
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#include "PortWrite_MCP23S17.h"
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const uint8_t PortIOE::DEVICE_ADDR = 0x20; //MCP23S17 address, all 3 ADDR pins are grounded
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PortIOE portA(0, 0);
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PortWrite_MCP23S17 portAWrite(portA); //PortAWrite needed for begin()
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//const uint8_t GPIOA = 0x12; //LEDs are on port A
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void setup()
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{
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delay(6000);
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portAWrite.begin();
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//Keyboard.print("start blinking");
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}
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void loop()
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{
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portAWrite.write(~0, HIGH); //set all GPIOA pins HIGH
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delay(2000);
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portAWrite.write(~0, LOW); //set all GPIOA pins LOW
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delay(2000);
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}
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