Psion Teklogix OMNii HDK XT10, Руководство пользователя

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Chapter 4: Software
Omnii HDK API Functions
42 Psion Teklogix Omnii HDK User Manual
Returns
• ERROR_SUCCESS – if successful.
• ERROR_INVALID_HANDLE – the specified handle is invalid.
• ERROR_INVALID_PARAMETER – the specified pin is not valid.
• ERROR_INVALID_DATA - an exception was generated.
• Other errors are possible.
Sample Code
4.7.4.9 Hdk7545_ExpansionGetPinDirection
Syntax
DWORD Hdk7545_ExpansionGetPinDirection( HANDLE hdk, DWORD pin,
Hdk7545_PinDirection *direction );
Parameters
• hdk – [in] an open HDK handle.
• pin – [in] the ID of the expansion connector pin. The pin parameter must be set to one of the
HDK7545_GPIO_PIN_EXPANSION_xxx values.
• direction – [out] a pointer to the current pin direction (input/output).
Description
Reports the current direction (input/output) for the specified pin.
Expansion connector pins can be configured for use as a GPIO interface, or they can be reassigned
to an alternate function (serial or SPI) using the Hdk7545_ExpansionSetPinFunction function (see
page 46). The pin direction does not need to be set if the alternate (non-GPIO) function for the pin
is enabled.
Drivers and/or applications must set the pin direction to output before calling the
Hdk7545_ExpansionSetPinState function.
// configure expansion 1's GPIO 0-3 pins (0, 3 as outputs, and 1, 2 as inputs).
DWORD SetDirection()
{
Hdk7545_Connector expansionSlot = Hdk7545_Connector_Expansion1;
HANDLE hdkHandle = INVALID_HANDLE_VALUE;
DWORD result = Hdk7545_Open(&hdkHandle, expansionSlot);
if( result != ERROR_SUCCESS ) {
return ERROR_NOT_SUPPORTED;
}
Hdk7545_ExpansionSetPinDirection(hdkHandle,
HDK7545_GPIO_PIN_EXPANSION_GPIO0_TXD,Hdk7545_PinDirection_Output);
Hdk7545_ExpansionSetPinDirection(hdkHandle,
HDK7545_GPIO_PIN_EXPANSION_GPIO1_RXD,Hdk7545_PinDirection_Input);
Hdk7545_ExpansionSetPinDirection(hdkHandle,
HDK7545_GPIO_PIN_EXPANSION_GPIO2_CTSN,Hdk7545_PinDirection_Input);
Hdk7545_ExpansionSetPinDirection(hdkHandle,
HDK7545_GPIO_PIN_EXPANSION_GPIO3_RTSN,Hdk7545_PinDirection_Output);
Hdk7545_Close(&hdkHandle);
return ERROR_SUCCESS;
}