Datasheet

MCP2200
DS22228B-page 20  2011 Microchip Technology Inc.
2.3.1.19 ReadPinValue
Function:
int SimpleIOClass::ReadPinValue(unsigned int pin)
EXAMPLE 2-19:
2.3.1.20 ReadPort
Function:
b
ool SimpleIOClass::ReadPort(unsigned int *returnvalue)
EXAMPLE 2-20:
Summary: Reads the specified pin.
Description: Reads the specified pin and returns the value as the return value. If the pin has been configured as a
digital input, the return value will be either ‘
0’ or ‘1’. If an error occurs, the function will return a value
of 0x8000.
Precondition: Must be previously configured as an input via a
ConfigureIO call.
VID and PID must be previously set via a call to
InitMCP2200(VID, PID).
Parameters: pin - the pin number to set (0-7)
Returns: This function returns the read value of the pin, or returns a value of 0x8000, if an error occurs.
Remarks: None.
Summary: Reads the GPIO port as digital input.
Description: Reads the GPIO port and returns the value in
returnvalue. This provides a means to read all pins
simultaneously, instead of one-by-one.
Precondition: Must be previously configured as an input via a
ConfigureIO call.
VID and PID must be previously set via a call to
InitMCP2200(VID, PID).
Parameters: • pin - the pin number to set (0-7)
• returnvalue - the value read on the pin (‘0’ or ‘1’)
Returns: This function returns True if the transmission is successful and returns False if the transmission fails.
Remarks: Pins configured for output return the current state of the port. Pins configured as input read as zero.
unsigned int rv;
if (SimpleIOClass::ReadPinValue(0) != 0x8000)
{
lblStatusBar->Text = “Success”;
}
else
lblStatusBar->Text = “Invalid command ” + SimpleIOClass::LastError;
unsigned int rv;
if (SimpleIOClass::ReadGPIOPort (0, &rv))
{
lblStatusBar->Text = “Success”;
}
else
lblStatusBar->Text = “Invalid command ” + SimpleIOClass::LastError;