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## Description

These are some macros I wrote to make writing code for the LAB-X3 simpler. They include macros to do the following;

- Convert binary to decimal digits,
- Delay execution for a certain number of milliseconds
- A message declaration macro to store a string in CODE space
- A message sending macro to send that sort of message to the LCD

Basically syntactic sugar to lessen the pain of writing everything in assembly language!

## The Source Code

; vim: set syntax=pic : ; UTIL.INC - Utility Routines ; This Version 28-Dec-01 NOLIST ; Written by Chuck Manis (http://www.mcmanis.com/chuck) ; Copyright (c) 2001 Charles Manis, All Rights Reserved ; ; Change Log: ; 28-DEC-01 Added Digit conversion routines ; 22-DEC-01 Initially created with the WAIT ; macro for computing delays. ; ; NOTICE: THIS CODE COMES WITHOUT WARRANTY OF ANY KIND EITHER ; EXPRESSED OR IMPLIED. USE THIS CODE AT YOUR OWN RISK! ; I WILL NOT BE HELD RESPONSIBLE FOR ANY DAMAGES, DIRECT ; OR CONSEQUENTIAL THAT YOU MAY EXPERIENCE BY USING IT. ; ; * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * util_inc equ 0 ; ; Digit Conversion Macro ; ; This macro converts one "digit" of a 5 digit number ; into ASCII It is used in the routine CVT_NUM that ; converts the number in NUM_HIGH and NUM_LOW, into 5 ; ASCII digits stored in DIGIT_0, DIGIT_1, ... DIGIT_4. ; DIGIT_0 is the MSD, DIGIT_4 is the LSD. ; ; It works by initializing the DIGIT location to '0' - 1 (ASCII ; zero minus 1) and then begins subtracting the value you pass and ; counts how many times it can be subtracted before underflow (very ; simple divide operation). Then adds back the last value and returns. ; It leaves NUM_LOW and NUM_HIGH with a value that is the modulus ; of NUM % VALUE (the remainder) and DIGIT_n has the divider. ; ; Cycle computation : ; 3 preamble ; 10 per digit increment ; 6 postamble ; 19 + 10 * actual digit ; _ONE_DIGIT MACRO NUMBER, DIGITS, DIG_NUM, VALUE MOVLW '0' - 1 MOVWF DIGITS + #v( DIG_NUM ) LOCAL LOOP LOOP: INCF DIGITS + #v( DIG_NUM ),F MOVLW low (VALUE) ; Low byte of value SUBWF (NUMBER),F ; Count = count - value MOVLW high (VALUE) SKPC MOVLW (high (VALUE)) + 1 SUBWF (NUMBER)+1,F SKPNC GOTO LOOP ; Not done yet so loop MOVLW low (VALUE) ; Else add back VALUE ADDWF (NUMBER),F ; To the count MOVLW high (VALUE) SKPNC MOVLW (high (VALUE)) + 1 ADDWF (NUMBER)+1,F ENDM ; ; Call's DO_DIGIT 5 times to convert the number in 'NUMBER' ; into a string at 'DIGITS' ; BIN2ASCII MACRO NUMBER, DIGITS nolist _ONE_DIGIT NUMBER, DIGITS, 0, D'10000' _ONE_DIGIT NUMBER, DIGITS, 1, D'1000' _ONE_DIGIT NUMBER, DIGITS, 2, D'100' _ONE_DIGIT NUMBER, DIGITS, 3, D'10' MOVF (NUMBER),W ; Get last digit ADDLW '0' ; Add ascii 0 to it MOVWF ((DIGITS)+4) ; Store it in last digit CLRF (NUMBER) list ENDM ; ; Wait Macro ; ; This macro comes from the "Advanced" PIC programming seminar ; and it will build a delay of 'n' machine cycles which are ; 1/4 the clock frequency. So for a 4Mhz crystal a delay of ; 1 cycle is 4 ticks, or 1 instruction cycle which is 1uS. ; WAIT MACRO CYCLES nolist X SET (CYCLES) % 4 IF (X == 1) || (X == 3) NOP ENDIF IF (X == 2) || (X == 3) GOTO $+1 ENDIF X SET (CYCLES) / 4 IF (X) IF (X == 256) X SET 0 ENDIF MOVLW X ADDLW -1 SKPZ GOTO $-2 ENDIF list ENDM ; msg: MOVF INDEX,W ; ADDWF PCL ; DT <pos>,"The Message", 0 ; DM MACRO msg, index MOVF INDEX,W ADDWF PCL DT msg,0 ENDM ; ; Send a message to the LCD, the format of the message is ; <position>, text message, nul byte. ; No interpretation of special numbers is done at all. ; SENDMSG MACRO msg, index LOCAL LOOP,MSG_EXIT CLRW MOVWF index CALL msg CALL LCD_CMD LOOP: INCF index,F CALL msg ANDLW H'FF' SKPNZ GOTO MSG_EXIT CALL LCD_CHAR GOTO LOOP MSG_EXIT: ENDM LIST

## License

This work is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported License. You are free to play around with it and modify it but you are not licensed to use it for commercial purposes. Click the link above for more details on your rights under this license.