diff options
| -rw-r--r-- | cmpen472hw5_McDonnell/Sources/main.asm | 78 |
1 files changed, 43 insertions, 35 deletions
diff --git a/cmpen472hw5_McDonnell/Sources/main.asm b/cmpen472hw5_McDonnell/Sources/main.asm index 06b44c8..5ad91b3 100644 --- a/cmpen472hw5_McDonnell/Sources/main.asm +++ b/cmpen472hw5_McDonnell/Sources/main.asm @@ -65,6 +65,7 @@ SCIDRL equ $00CF ; Serial port (SCI) Data Register CR equ $0d ; carriage return, ASCII 'Return' key LF equ $0a ; line feed, ASCII 'next line' character +NULL equ $00 ; NULL Terminator character ************************************************************************** * Data Section: address used [ $3000 to $30FF ] RAM Memory @@ -78,6 +79,16 @@ Counter dc.w $0036 ; X register count number for time Delay LEVEL dc.b $0005 ; Light Level that the LED should be +msg dc.b 'L1: Turn on LED1',CR,LF, + 'F1: Turn off LED1',CR,LF + 'L2: Turn on LED2',CR,LF + 'F2: Turn off LED2',CR,LF + 'L3: Turn on LED3',CR,LF + 'F3: Turn off LED3',CR,LF + 'L4: LED4 goes from 0% light level to 100% light level in 0.4 seconds',CR,LF + 'F4: LED4 goes from 100% light level to 0% light level in 0.4 seconds',CR,LF + 'QUIT: Quit menu program, run \'Type writer\' program.',CR,LF,NULL + * ************************************************************************** * Program Section: address used [ $3100 to $3FFF ] RAM Memory @@ -89,6 +100,8 @@ pgstart lds #$3100 ; initialize the stack pointer staa DDRB ; set PORTB bit 4,5,6,7 as output mainLoop + ldx msg + jsr WriteString bra mainLoop ; Loop back to mainLoop always ************************************************************************** @@ -283,43 +296,38 @@ innerLoop dex ; decrement register x by 1 nop ; extra nop to make exactly 10 usec rts ; return to caller -;***************putchar************************ -;* Program: Send one character to SCI port, terminal -;* Input: Accumulator A contains an ASCII character, 8bit -;* Output: Send one character to SCI port, terminal -;* Registers modified: CCR -;* Algorithm: -; Wait for transmit buffer become empty -; Transmit buffer empty is indicated by TDRE bit -; TDRE = 1 : empty - Transmit Data Register Empty, ready to transmit -; TDRE = 0 : not empty, transmission in progress -;********************************************** -putchar brclr SCISR1,#%10000000,putchar ; wait for transmit buffer empty - staa SCIDRL ; send a character - rts -;***************end of putchar***************** +;************************************************************************* +; putchar subroutine +; +; This subroutine writes a single byte to a serial line +; +; Input: A single ASCII byte in accumulator A +; Output: Sends one character to SCI port +; Registers in use: Accumulator A with input byte +; Memory locations in use: SCISR1 and SCIDRL status and data registers +; + +putchar brclr SCISR1,#%10000000,putchar ; wait for transmit buffer empty + staa SCIDRL ; send a character + rts ; Return to caller + +;************************************************************************* +; putchar subroutine +; +; This subroutine reads one byte from the SCI port +; +; Input: One byte from the SCI port +; Output: One byte in accumulator A +; Registers in use: Accumulator A for output byte +; Memory locations in use: SCISR1 and SCIDRL status and data registers +; +getchar brclr SCISR1,#%00100000,getchar7 ; If no input on SCI port, return 0 + ldaa SCIDRL ; Read one byte from SCI port into A + rts ; Return to caller +getchar7 clra ; Set A to 0 + rts ; Return to caller -;****************getchar*********************** -;* Program: Input one character from SCI port (terminal/keyboard) -;* if a character is received, other wise return NULL -;* Input: none -;* Output: Accumulator A containing the received ASCII character -;* if a character is received. -;* Otherwise Accumulator A will contain a NULL character, $00. -;* Registers modified: CCR -;* Algorithm: -; Check for receive buffer become full -; Receive buffer full is indicated by RDRF bit -; RDRF = 1 : full - Receive Data Register Full, 1 byte received -; RDRF = 0 : not full, 0 byte received -;********************************************** -getchar brclr SCISR1,#%00100000,getchar7 - ldaa SCIDRL - rts -getchar7 clra - rts -;****************end of getchar**************** end ; last line of the file |