Bolymin BE220C, Руководство пользователя

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BE220C USER MANUAL - 64 -
3.4 GPIO Control
3.4.1 How to Control GPIO for BE220C
Bolymin provides a DLL file “
pGPIO_220A.dll
”,which is already included in your WinCE OS as a
hidden file, to control the General Purpose Input and Ouput(GPIO) signal. In BEGA220A, there
are 12 user defined GPIO. User may read current value of all GPIO of BEGA220A, change
values of GP output signal and set the attribute of GPIO by functions in “
pGPIO_220A.dll
”.
User may use GPIO control functions by following procedures:
STEP 1.
Add
“pGPIO_220A.h”
into project.
STEP 2.
Load “
pGPIO_220A.dll
” by “
Loadlibrary
()” function.
STEP 3 .
Get the address of control functions by “
GetProcAddress
()” function.
STEP 4.
Execute GPIO control functions by the address got at STEP3.
Below is a simple example code to use the GPIO control functions:
// variable declaration
HINSTANCE m_hModule;
BOOL (*m_pGetGPInput)(int);
void (*m_pSetGPOutput)(int, BOOL);
BOOL (*m_pIsOutput)(int);
void (*m_pSetIOAttribute)(int, BOOL);
m_hModule=::LoadLibrary(_T("
pGPIO_220A.dll
"));
m_pGetGPInput = (BOOL (*)(int))::GetProcAddress(m_hModule,_T("GetGPInput"));
m_pSetGPOutput = (void (*)(int, BOOL))::GetProcAddress(m_hModule,_T("SetGPOutput"));
m_pIsOutput = (BOOL (*)(int))::GetProcAddress(m_hModule,_T("IsOutput"));
m_pSetIOAttribute = (void (*)(int, BOOL))::GetProcAddress(m_hModule,_T("SetIOAttribute"));
m_pSetIOAttribute(GIO_KEY1, GA_INPUT);
m_bPOUT1 = m_pGetGPInput(GIO_KEY1);
m_pSetIOAttribute(GIO_KEY1, GA_OUTPUT);
if (m_pIsOutput(GIO_KEY1))
m_pSetGPOutput(GIO_KEY1, TRUE);
Load “ pGPIO_220A.dll ” and get the address of
GPIO control functions.
Execute GPIO control functions.