-6. SysIOAPI.DLLThis DLL provide hardware relative API for user to control scanner, LED, back-light and PCcard slot. API functions are provided through DLL to assist programmer to write applicationfor PA600.Note : For PA600 programming, it need to dynamically load DLL for using Unitech built-in DLL (Unitechwill not provide *.H and *.LIB for compiler), please refer to Chapter 8 for programming guide.6.1. Keypad Related Functions6.1.1. Disable/enable power buttonFunction Description:To enable / disable power buttonFunction call:VOID DisablePowerButton (BOOL)Parameter (Input)TRUE = Disable power button.FALSE = Enable power button.Return code:None6.1.2. Set keypad utility input modeFunction Description:In terminal, there is a utility to emulate full alpha key input, called GetVK. Theinput mode can be switched by pressing “alpha” key, or by following function.Function call:void SetGetVKWorkingMode(int)Parameter (input)0 = hide the selection window.1 = show lower case selection window.2 = show upper case selection window.Return code:None6.1.3. Get keypad utility input modeFunction Description:This function is used to check alpha key input mode.Function call:BYTE GetAlphaKeyWorkingMode(void);Return code:0 = normal .1 = lower case.2 = upper case.6.1.4. Check Alpha key is pressingFunction Description:This function is used to check if alpha key is pressed or not.Function call:BOOL GetKeypadAlphaKeyStatus(void);Return code:TRUE = Alpha key is pressed.FALSE = Alpha key is released.