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- #include "PortRead_MCP23S17.h"
-
- /*
- PortRead_MCP23S17::begin() is not needed because port direction is already configured to input by default.
- SPI bus is configured in PortWrite_MCP23S17::begin().
- */
-
- /*
- returns port value
- */
- uint8_t PortRead_MCP23S17::read()
- {
- uint8_t portState; //bit wise
-
- //slower clock
- digitalWrite(SS, LOW); //enable Slave Select
- SPI.transfer(port.ADDR << 1 | 1); //read command
- SPI.transfer(port.num + 0x12); //register address to read data from
- portState = SPI.transfer(0); //save the data (0 is dummy data to send)
- digitalWrite(SS, HIGH); //disable Slave Select
-
- return portState;
- }
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