EMS6500 EM Microelectronic, EMS6500 Datasheet - Page 54

• Manufacturer Part Number: EMS6500
• Description: Microcontroller Development System 4-bit (Emmon), Simulators 4-bit
• Manufacturer: EM Microelectronic

Copyright  2003, EM Microelectronic-Marin SA
4.4.
4.5.
Elements must be separated by one or more TAB (ASCII 9) or SPACE characters.
Comments must begin with a semi-colon (;). Only labels are written starting in
column 1 of the text line.
Embedded COMMENTS can be included in any statement and are taken to be all
characters to the right of a semi-colon (;). This is standard practice of most
assemblers and fully supported by EM66xx assembler.
;Embedded single-line Comment (accepted by most Assemblers)
Only labels are written starting in column 1 of the text line (or comments as
described above), and when assembled are allocated the memory address of the
instruction. These can then be used within an EXPRESSION to automatically
reference the 'tagged' instruction address. Assembler "pseudo-op" directives may
also require a LABEL as part of the syntax. Syntax rules for labels are:
Unlimited length.
All characters are significant.
May include only uppercase and lowercase letters, digits and the underscore
character ( A .. Z, a .. z, 0 .. 9, _ ).
Cannot begin with digits ( 0 .. 9 ).
May be terminated with a colon ( : ).
Examples of acceptable and non-valid symbols are given below:
ROOX0
LOOP1
Mem_Setting
RESET:
0POS
LP*1 ;illegal - contains expression character
RESET:1
Stipulation of LABEL syntax rules is to avoid incorrect evaluation or
misinterpretation. For instance, '0POS' would be assumed to be a numeric constant
as it begins with 0, consequently an eventual 'Syntax Error' would be generated
when it is referenced by an instruction.
Embedded Documentation
Symbol Syntax Rules
;illegal - contains ':'
;Valid Label Examples
;':' allowed if last character
;illegal - begins with 0
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Development System
www.emmicroelectronic.com
EM66xx
Binder 4.3-01/03 Rev. B/495