Hey Ted,

The zero ("0") is put before the hex character (in your example "C") because
it indicates to the assembler that it is a constant value.

Without the zero, the assembler would encounter the string "Ch", which it
would assume is a label.

When I'm doing PC assembly language, this one always bites me on the bum -
It's easy to write "10h" (which will be correctly interpreted as 16 decimal)
and then follow with "AAh" which is going to be initially interpreted as a
label.

This is why I prefer a definite type prefix like "0x0" or "$".

myke

----- Original Message -----
From: "Ted Mawson" <Ted.Mawson@PORTFOLIOPM.COM>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Friday, January 18, 2002 8:47 PM
Subject: [PIC]: Confusion on hex format?


> I'm following the assembly code in worktime.asm to get me (back) up to
> speed on assembly language.
>
>
>
> There's a bit where it goes.
>
>
>
> ;  Macro
>
> EStrobe MACRO                   ;  Strobe the "E" Bit
>   bsf    E
>   bcf    E
>  ENDM
>
>             CBLOCK     0CH
>                 sec             ; seconds digit
>                 sec10           ; 10's of second digit
>                 mins            ; minutes digit
>                 min10           ; 10's of minutes digit
>                 hr              ; hours digit
>                 hr10            ; 10's of hours digit
>                 highlim         ; high limit + 1 of digit
>                 w_temp          ; holds W during interrupt
>                 status_temp     ; holds STATUS during interrupt
>                 fsr_temp        ; holds FSR during interrupt
>                 Dlay            ; 8 Bit Delay Variable
>                 working         ; working flag 0 not working, 1 working
>                 ptr             ; used in displaying message
>                 Temp            ; a temporary variable
>                 bin             ; a temporary variable
>                 oset            ; offset of time register
>                 oldtime         ; holds last value of sec
>                ENDC
>
>
>
> Here's my question - CBLOCK defines a block of constants starting at a
> given address.  Problem is, 0CH isn't a valid address - or is it?  If it
> is, why does it have a '0' in the lead position? 0xCH isn't valid as H
> is one too many for hex?  I expect I'm being dumb but, can someone
> please point me to my mistake?
>
>
>
> Ted Mawson
>
> www.portfoliopm.com
>
> --
> http://www.piclist.com hint: The list server can filter out subtopics
> (like ads or off topics) for you. See http://www.piclist.com/#topics
>
>
>

--
http://www.piclist.com hint: The list server can filter out subtopics
(like ads or off topics) for you. See http://www.piclist.com/#topics