Mikroelektronika MIKROE-738 Datenbogen

mikroC PRO for PIC32

MikroElektronika

397

Ps2_Config

Ps2_Key_Read

void Ps2_Config();

Description Initializes the MCU for work with the PS/2 keyboard.
Parameters None.
Returns

Nothing.

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 defined before using this function.

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;

...

Ps2_Config();         // Init PS/2 Keyboard

None.

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 flag 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. 

- 

1

 if reading of a key from the keyboard was successful 

- 

0

 if no key was pressed 

PS/2 keyboard needs to be initialized. See Ps2_Config routine.

unsigned short keydata = 0, special = 0, down = 0;

...

do {

  if (Ps2_Key_Read(&keydata, &special, &down)) {

    if (down && (keydata == 16)) break;

  }

} while (1);

None.