Mikroelektronika MIKROE-350 Datenbogen

This simple example reads values of the pressed keys on the PS/2 keyboard and
sends them via UART.

program PS2_Example

dim keydata, special, down as byte

dim PS2_Data          as sbit at PINC.B0

PS2_Clock_Input   

as sbit at PINC.B1

PS2_Clock_Output  

as sbit at PORTC.B1

PS2_Data_Direction  

as sbit at DDRC.B0

PS2_Clock_Direction 

as sbit at DDRC.B1

main:

UART1_Init(19200)        ' Initialize UART module at 19200 bps
Ps2_Config()             ' Init PS/2 Keyboard

Delay_ms(100)            ' Wait for keyboard to finish

UART1_Write("R")         ' Ready

while TRUE                                                   '

Endless loop

if (Ps2_Key_Read(keydata, special, down) <> 0) then

' If

data was read from PS/2

if (((down <> 0) and (keydata = 16)) <> 0) then

'

Backspace read

UART1_Write(0x08)                                      '

Send Backspace to USART terminal

else if (((down <> 0) and (keydata = 13)) <> 0) then

'

Enter read

UART1_Write(10)                                      '

Send carriage return to usart terminal

UART1_Write(13)                                      '

Uncomment this line if usart terminal also expects line feed

'   for new line transition

else if (((down <> 0) and (special = 0) and (keydata <>

0)) <> 0) 

' Common key read

UART1_Write(keydata)                             '

Send key to usart terminal

Delay_ms(10)                              ' Debounce period

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CHAPTER 6