wolfv6
7 years ago
6 changed files with 34 additions and 19 deletions
+ 16
- 6
src/PortRead_MCP23S17.cpp
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| @@ -4,26 +4,36 @@ | |||
| PortRead_MCP23S17::begin() is not needed because port direction is already configured to input by default. | |||
| SPI bus is configured in PortWrite_MCP23S17::begin(). | |||
| */ | |||
| void PortRead_MCP23S17::begin() | |||
| void PortRead_MCP23S17::begin(const uint8_t strobeOn) | |||
| { | |||
| uint8_t pullUp; //bitwise, 1 means internal pull-up resistor enabled | |||
| if (strobeOn == LOW) //if active low | |||
| { | |||
| pullUp = readPins; | |||
| } | |||
| else | |||
| { | |||
| pullUp = 0; | |||
| } | |||
| pinMode(SS, OUTPUT); //configure controller's Slave Select pin to output | |||
| digitalWrite(SS, HIGH); //disable Slave Select | |||
| SPI.begin(); | |||
| SPI.beginTransaction(SPISettings (SPI_CLOCK_DIV8, MSBFIRST, SPI_MODE0)); //control SPI bus todo is slow clock needed? | |||
| digitalWrite(SS, LOW); //enable Slave Select | |||
| digitalWrite(SS, LOW); //enable Slave Select | |||
| SPI.transfer(port.ADDR << 1); //write command | |||
| SPI.transfer(port.num); //configure IODIR | |||
| SPI.transfer(pullUp); //0=output (for LED), 1=input (for read) | |||
| SPI.transfer(readPins); //0=output (for LED), 1=input (for read) | |||
| digitalWrite(SS, LOW); //enable Slave Select | |||
| digitalWrite(SS, HIGH); //disable Slave Select | |||
| digitalWrite(SS, HIGH); //disable Slave Select | |||
| SPI.transfer(port.ADDR << 1); //write command | |||
| SPI.transfer(port.num + 0x0C); //configure GPPU | |||
| SPI.transfer(pullUp); //0=pull-up disabled (for LED), 1=pull-up enabled (for read) | |||
| digitalWrite(SS, HIGH); //disable Slave Select | |||
| //SPI.endTransaction() is not called to release the SPI bus | |||
| // because keyboard only has one SPI device. | |||
| } | |||
+ 6
- 5
src/PortRead_MCP23S17.h
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| @@ -5,12 +5,13 @@ | |||
| #include <SPI.h> | |||
| #include <PortRead.h> | |||
| #include "PortIOE.h" | |||
| #include "Scanner_Port.h" | |||
| /* One MCP23S17 I/O expander port connected to matrix columns. | |||
| Instantiation todo | |||
| ------------ | |||
| pullUp parameter is port's bitwise pin configuration | |||
| readPins parameter is port's bitwise pin configuration | |||
| 1=configure as input (for pins connected to column) | |||
| 0=configure as output (for LED or not connected to a column) | |||
| @@ -21,17 +22,17 @@ Example instantiation for column port 1, with pins 2 and 3 connected to columns: | |||
| PortIOE port1(1, 0); | |||
| PortRead_MCP23S17 colPort1(port1, 2<<0 | 1<<3 ); | |||
| pullUp are read from pin 0 on up. | |||
| readPins are read from pin 0 on up. | |||
| */ | |||
| class PortRead_MCP23S17 : public PortRead | |||
| { | |||
| private: | |||
| PortIOE& port; | |||
| const uint8_t pullUp; //bitwise, 1 means internal pull-up resistor enabled | |||
| const uint8_t readPins; //bitwise, 1 means internal pull-up resistor enabled | |||
| public: | |||
| PortRead_MCP23S17(PortIOE& port, const uint8_t pullUp) : port(port), pullUp(pullUp) {} | |||
| void begin(); | |||
| PortRead_MCP23S17(PortIOE& port, const uint8_t readPins) : port(port), readPins(readPins) {} | |||
| void begin(const uint8_t strobeOn); | |||
| virtual uint8_t read(); | |||
| }; | |||
| #endif | |||
+ 7
- 7
src/PortWrite_MCP23S17.cpp
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| @@ -29,20 +29,20 @@ void PortWrite_MCP23S17::begin() | |||
| } | |||
| /* | |||
| pin is bitwise, where pin being strobed is 1. | |||
| strobe is HIGH or LOW (for active high or active low). | |||
| strobePin is bitwise, where pin being strobed is 1. | |||
| pinLogicLevel is HIGH or LOW. | |||
| port.outputVal can be shared by LEDs. | |||
| The functions does not reset the other pins so that they can be used for LEDs. | |||
| */ | |||
| void PortWrite_MCP23S17::write(const uint8_t pin, const bool strobe) | |||
| void PortWrite_MCP23S17::write(const uint8_t strobePin, const uint8_t pinLogicLevel) | |||
| { | |||
| if (strobe == LOW) //if active low | |||
| if (pinLogicLevel == LOW) | |||
| { | |||
| port.outputVal &= ~pin; //set pin output to low | |||
| port.outputVal &= ~strobePin; //set strobePin output to low | |||
| } | |||
| else //if active high | |||
| else | |||
| { | |||
| port.outputVal |= pin; //set pin output to high | |||
| port.outputVal |= strobePin; //set strobePin output to high | |||
| } | |||
| writePort(port.num + 0x12, port.outputVal); //set GPIO port pins for stobe and LEDs | |||
+ 1
- 1
src/PortWrite_MCP23S17.h
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| @@ -41,6 +41,6 @@ class PortWrite_MCP23S17 : public PortWrite | |||
| public: | |||
| PortWrite_MCP23S17(PortIOE& port) : port(port) {} | |||
| void begin(); | |||
| virtual void write(const uint8_t pin, const bool level); | |||
| virtual void write(const uint8_t pin, const uint8_t level); | |||
| }; | |||
| #endif | |||
+ 4
- 0
unit_tests/PortRead_MCP23S17/PortRead_MCP23S17.ino
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| @@ -9,6 +9,10 @@ http://arduino.stackexchange.com/questions/28792/reading-an-mcp23s17-i-o-expande | |||
| */ | |||
| #include "PortIOE.h" | |||
| #include "PortRead_MCP23S17.h" | |||
| #include "Scanner_Port.h" | |||
| const bool Scanner_Port::STROBE_ON = LOW; | |||
| const bool Scanner_Port::STROBE_OFF = HIGH; | |||
| const uint8_t PortIOE::ADDR = 0x20; //MCP23S17 address, all 3 ADDR pins are grounded | |||
| PortIOE portB(1, 0); | |||