.title "EL308" .sbttl "Keys that beep" .equ __24FJ256GB110, 1 .include "p24FJ256GB110.inc" .global __reset ;The label for the first line of code. .global __T1Interrupt ;Declare Timer 1 ISR name global .global __T2Interrupt ;Declare Timer 2 ISR name global .global __CNInterrupt .bss LCD_line1: .space 16 LCD_line2: .space 16 LCD_ptr: .space 2 LCD_cmd: .space 2 LCD_offset: .space 2 KPD_buff: .space 2 KPD_stat: .space 2 .section .const,psv line1: .ascii "Keypad -> " line2: .ascii " " lookup: .ascii "0123456789ABCDEF" .text ;Start of Code section __reset: mov #__SP_init, W15 ; Initalize the Stack Pointer mov #__SPLIM_init, W0 ; Initialize the Stack Pointer Limit Register mov W0, SPLIM nop ; Add NOP to follow SPLIM initialization ;<> call init_PSV call init_LED call init_LCD call init_message call init_keypad call init_buzzer call init_timer call init_timer2 MainLoop: mov KPD_stat, W0 cp0 W0 bra Z, NoKey mov KPD_buff, W0 mov #psvoffset(lookup), W1 mov.b [W1+W0], W2 mov #LCD_line1, W0 mov.b W2, [W0+10] NoKey: clrwdt bra MainLoop ; ----------------------------------------------------- ; !!!!!!!!!!!!!!!!!! Functions !!!!!!!!!!!!!!!!!!!!!!!! ; ----------------------------------------------------- __CNInterrupt: push W0 push W1 bclr IFS1, #CNIF mov PORTD, W0 btss W0, #6 bra key_released mov #0x000F, W1 and W0, W1, W0 mov W0, KPD_buff mov #1, W0 mov W0, KPD_stat bset T2CON, #TON ; turn timer2 ON bset PORTD, #13 ; turn buzzer ON key_released: pop W1 pop W0 retfie __T2Interrupt: push W0 push W1 bclr IFS0, #T2IF ; clear timer2 interrupt status flag bclr T2CON, #TON ; turn timer2 OFF bclr PORTD, #13 ; turn buzzer OFF mov #0x0000, W0 mov W0, TMR2 ; clear TMR2 register pop W1 pop W0 retfie init_timer2: bclr T2CON, #TON ; turn timer2 OFF bset T2CON, #TCKPS1 bclr T2CON, #TCKPS0 ; set prescaler to 64 bclr T1CON, #TCS ; select internal clock mov #0x0000, W0 mov W0, TMR2 ; clear TMR2 register mov #7813, W0 mov W0, PR2 ; set timer2 period to 32150 -> f=2e6/64/7813=4 Hz bclr IPC1, #T2IP2 bclr IPC1, #T2IP1 bset IPC1, #T2IP0 ; set timer2 priority to 001 bclr IFS0, #T2IF ; clear timer2 interrupt status flag bset IEC0, #T2IE ; enable timer1 interrupts ; bset T2CON, #TON ; turn timer2 ON return init_PSV: mov #psvpage(line1), W0 mov W0, PSVPAG ; set PSVPAG to page that contains hello bset.b CORCONL,#PSV ; enable Program Space Visibility return init_timer: bclr T1CON, #TON ; turn timer1 OFF bset T1CON, #TCKPS1 bset T1CON, #TCKPS0 ; set prescaler to 256 bclr T1CON, #TCS ; select internal clock mov #0x0000, W0 mov W0, TMR1 ; clear TMR1 register mov #0x0040, W0 mov W0, PR1 ; set timer1 period to 0x0040 -> f=2e6/256/64=122 Hz bclr IPC0, #14 bclr IPC0, #13 bset IPC0, #12 ; set timer1 priority to 001 bclr IFS0, #T1IF ; clear timer1 interrupt status flag bset IEC0, #T1IE ; enable timer1 interrupts bset T1CON, #TON ; turn timer1 ON return init_LED: bclr TRISF, #0 bclr TRISF, #1 bclr TRISF, #2 bclr TRISF, #3 ; LED array return init_LCD: bclr TRISB, #15 bclr PORTD, #4 ; make sure LCD is disabled before port is set to output mode bclr TRISD, #4 bclr TRISD, #5 mov #0xFF00, W0 mov W0, TRISE bclr PORTD, #5 ; select LCD WR mode mov #0x0038, W0 ; init LCD call sendcomm call dly call dly call dly mov #0x000C, W0 ; LCD on, cursor off call sendcomm mov #0x0001,W0 ; clear LCD call sendcomm return sendcomm: bclr PORTB,#15 ; select LCD command register mov W0, PORTE ; output command bset PORTD, #4 call dly nop bclr PORTD, #4 call dly return dly: mov #0x2000,W0 dlyloop: sub W0, #1, W0 bra NZ, dlyloop return init_message: mov #0x0000, W0 mov W0, LCD_ptr mov W0, LCD_offset mov #0x00C0, W0 mov W0, LCD_cmd mov #psvoffset(line1), W1 mov #LCD_line1, W2 repeat #15 mov.b [W1++], [W2++] mov #psvoffset(line2), W1 mov #LCD_line2, W2 repeat #15 mov.b [W1++], [W2++] return init_keypad: bset TRISD,#0 ; DATA A bset TRISD,#1 ; DATA B bset TRISD,#2 ; DATA C bset TRISD,#3 ; DATA D bset TRISD,#6 ; DATA Available bclr IFS1, #CNIF ; clear CN interrupt flag bclr IPC4, #CNIP2 bclr IPC4, #CNIP1 bset IPC4, #CNIP0 ; set CN interrupt priority to 001 bset CNEN1, #CN15IE ; enable interrupts for CN15 (port D bit 6) bset IEC1, #CNIE ; enable CN interrupt mov #0, W0 mov W0, KPD_stat return init_buzzer: bclr PORTD, #13 ; buzzer initially OFF bclr TRISD, #13 ; enable output return ;.............................................................................. ;Timer 1 Interrupt Service Routine ;Example context save/restore in the ISR performed using PUSH.D/POP.D ;instruction. The instruction pushes two words W4 and W5 on to the stack on ;entry into ISR and pops the two words back into W4 and W5 on exit from the ISR ;.............................................................................. __T1Interrupt: push.s push.d W4 ; Save context using double-word PUSH ;<> bclr IFS0, #T1IF ; Clear the Timer1 Interrupt flag Status ; bit. clrwdt ; !!!!!!!!!!!! Very bad practice! !!!!!!!!!!!!!!!! mov LCD_ptr, W2 mov #0x0010, W1 cp W1, W2 bra NZ, send_LCD_data mov LCD_cmd, W0 bclr PORTB, #15 ; select LCD command register mov W0, PORTE ; output command bset PORTD, #4 nop bclr PORTD, #4 btg W0, #6 mov W0, LCD_cmd mov #0x0000, W2 mov W2, LCD_ptr mov LCD_offset, W0 btg W0, #4 mov W0, LCD_offset btg PORTF, #2 bra done_T1interrupt send_LCD_data: mov LCD_offset, W3 add W3, W2, W3 mov #LCD_line1, W1 mov.b [W1+W3], W0 bset PORTB, #15 ; select LCD data register mov W0, PORTE ; output command bset PORTD, #4 nop bclr PORTD, #4 inc W2, W2 mov W2, LCD_ptr done_T1interrupt: pop.d W4 ;Retrieve context POP-ping from Stack pop.s retfie ;Return from Interrupt Service routine ;--------End of All Code Sections --------------------------------------------- .end ;End of program code in this file