I'm hardly a PIC assembler expert these days -  but my suggection is
that you shouldn't need to define porta etc as they are already
defined in the include file. However they may be in upper case. There
is a switch somewhere that turns case sensitivity off.
Where you need to define constants use ".def" rather than "#define".
This is a common difference between C and assembler formats. Sometimes
it works, sometimes it doesn't - depending on the assembler.

Where you have defined porta etc. you need to to assign a value to it.
I suggest you open the include file "P16F877.inc" and look at whats
there & how it's formatted there.

RP

On 10/10/05, Ed Edmondson <dredwinphd@bresnan.net> wrote:
>  I have been trying to get this very small program to compile, however,
> below are the program code and error messages I received. I get 15 errors
> about symbols not being defined. I found what the 113 error was in an
> excerpt of chapter 8 of the Assembler/Linker/Librarian Users guide. 113 is
> "Symbol not previously defined" I tried to add #define to the program with
> only minor success. See below: I may not be the brighest coal in the fire
> but I will be the most persistent.
>
>  ;testprog.asm
> ;
> ; 8th October 2005
> ;
> ; LED blinky
>
>   list P = 16F877
>   include "P16F877.inc"
>
>  errorlevel -302, -305, -306
>
> ; turn off some MPASM messages
>
> ; 302 not in bank0
> ; 305 default destination of 1
> ; 306 crossing page boundary
> ; 113 symbol not previously defined "Can't disable this error code"
>
> ; Instruction cycle time = 400ns with 10MHz crystal
>
> ;set configuration
>
>  __CONFIG _CP_OFF & _WRT_ENABLE_ON & _HS_OSC & _WDT_OFF & _PWRTE_OFF &
> _BODEN_OFF & _LVP_OFF & _CPD_OFF & _DEBUG_OFF
>
>         cblock 0x20
>
>         varname1             ;some variables
>         varname2
>         varname3
>
>         endc
>
> ; define a pin name
>
> #define  led     portb,1      ;pin to drive LED
> #define porta
> #define portb
> #define portc
> #define portd
> #define porte
> #define trisa
> #define trisb
> #define trisc
> #define trisd
> #define option_reg
>
> ;program address start in memory
>
>         org     0x00         ;start address
>         goto    delay
>
> ; interrupt vector
>
> ;         org     0x04         ;REM if interrupts not used
> ;         goto    isr          ;REM if interrupts not used
>
> init     clrf    status       ;bank0
>
>         clrf    porta
>         clrf    portb
>         clrf    portc
>         clrf    portd
>         clrf    porte
>
>         banksel trisa        ;set data direction on pins
>
>         movlw   b'00000000'  ;all PortA as output
>         movwf   trisa
>
>
>         movlw   b'00000000'  ;all PortB as output
>         movwf   trisb
>
>
>         movlw   b'10000000'  ;all PortC as output
>         movwf   trisc
>
>         movlw   b'10000000'  ;all PortD as output
>         movwf   trisd
>
>         movlw   b'10000000'
> ;                  1           internal pull-ups off
>
>         movwf   option_reg   ;INTEDG = 0, falling edge for microswitch
>
>         banksel porta        ;return to bank0
>
> ;===============================================
>
> led_loop bsf     led          ;turn LED on
>         call    delay        ;0.2s delay
>         bcf     led          ;turn LED off
>         call    delay        ;0.2s delay
>         goto    led_loop     ;blink forever (what a life)
>
> delay    movlw   .56          ;call 1ms delay 200 times
>         movwf   varname1
> ms1      call    msec01
>         incfsz  varname1
>         goto    ms1
>         return
>
> msec01   movlw   .30          ;delay approx 1ms @ 10MHz
>         movwf   varname2
> loop     nop
>         nop
>         nop
>         nop
>         nop
>         nop
>         nop
>         nop
>         incfsz  varname2
>         goto    loop
>         return
>
>  end
>
>
> Clean: Deleting intermediary and output files.
> Clean: Done.
> Executing: "I:\Program Files\Microchip\MPASM Suite\MPAsmWin.exe" /q /p16F877
> "testprog.asm" /l"testprog.lst" /e"testprog.err" /o"testprog.o"
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 48 : Symbol not previously defined
> (status)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 50 : Symbol not previously defined
> (porta)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 51 : Symbol not previously defined
> (portb)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 52 : Symbol not previously defined
> (portc)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 53 : Symbol not previously defined
> (portd)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 54 : Symbol not previously defined
> (porte)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 56 : Symbol not previously defined
> (trisa)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 59 : Symbol not previously defined
> (trisa)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 63 : Symbol not previously defined
> (trisb)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 67 : Symbol not previously defined
> (trisc)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 70 : Symbol not previously defined
> (trisd)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 75 : Symbol not previously defined
> (option_reg)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 77 : Symbol not previously defined
> (porta)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 81 : Symbol not previously defined
> (portb)
> Error[113]   I:\MPLAB FILES\TESTPROG.ASM 83 : Symbol not previously defined
> (portb)
> Halting build on first failure as requested.
> BUILD FAILED: Sat Oct 08 18:16:53 2005
>
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