hexdump.mos

% STD
!ICO ? NIP <- #HLT

loop:
; Read one word into RES
RES <- IDA

; Print the 4 hex digits of RES
NIP <- #rotate_and_print_digit
NIP <- #rotate_and_print_digit
NIP <- #rotate_and_print_digit
NIP <- #rotate_and_print_digit

counter <- INC <- counter

; Stop if there is no more input
!ICO ? NIP <- #stop

DBG <- counter
ALX <- counter
ALY <- #16
EQU ? NIP <- #reset

PRN <- #' '
NIP <- #loop


reset:
counter <- #0
PRN <- #10 ; Print newline
NIP <- #loop

stop:
PRN <- #10 ; Print newline at the end
NIP <- #HLT

rotate_and_print_digit:
; Rotate RES 4 times to the left
RES <- LRO <- LRO <- LRO <- LRO <- RES

; Add the lower 4 bits to the address of
; hex_chars and print the character
ALX <- RES
ALY <- #$000F
ALX <- AND
ALY <- #hex_chars
PRN <- *SUM

; Return to the caller
NIP <- PIP

hex_chars:
"0123456789ABCDEF"
counter: 0