User manual

mikroC PRO for dsPIC
MikroElektronika
453
Ps2_Cong
Ps2_Key_Read
Prototype
void Ps2_Cong();
Description Initializes the MCU for work with the PS/2 keyboard.
Parameters None.
Returns Nothing.
Requires Global variables :
- PS2_Data: Data signal line
- PS2_Clock: Clock signal line
- PS2_Data_Direction: Direction of the Data pin
- PS2_Clock_Direction: Direction of the Clock pin
must be dened before using this function.
Example
// PS2 pinout denition
sbit PS2_Data at RB0_bit;
sbit PS2_Clock at RB1_bit;
sbit PS2_Data_Direction at TRISB0_bit;
sbit PS2_Clock_Direction at TRISB1_bit;
// End of PS2 pinout denition
...
Ps2_Cong(); // Init PS/2 Keyboard
Notes None.
Prototype
unsigned int Ps2_Key_Read(unsigned short *value, unsigned short *special,
unsigned short *pressed);
Description The function retrieves information on key pressed.
Parameters - value: holds the value of the key pressed. For characters, numerals, punctuation marks, and space
value will store the appropriate ASCII code. Routine “recognizes” the function of Shift and Caps Lock,
and behaves appropriately. For special function keys see Special Function Keys Table.
- special: is a ag for special function keys (F1, Enter, Esc, etc). If key pressed is one of these,
special will be set to 1, otherwise 0.
- pressed: is set to 1 if the key is pressed, and 0 if it is released.
Returns - 1 if reading of a key from the keyboard was successful
- 0 if no key was pressed
Requires PS/2 keyboard needs to be initialized. See Ps2_Cong routine.
Example
unsigned short keydata = 0, special = 0, down = 0;
...
// Press Enter to continue:
do {
if (Ps2_Key_Read(&keydata, &special, &down)) {
if (down && (keydata == 16)) break;
}
} while (1);
Notes None.