M68ICS05KJ Freescale Semiconductor, M68ICS05KJ Datasheet - Page 76

• Manufacturer Part Number: M68ICS05KJ
• Description: SIM PROGRAM FOR 68HC705KJ/J1A
• Manufacturer: Freescale Semiconductor
• Type: Simulator/Programmerr

Specifications of M68ICS05KJ

• Contents: Programmer, Power Supply, Assembler/Simulator/Debugger, Cable, Software and Documentation
• For Use With/related Products: 68HC705KJ/JIA
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

ASSEMBLER INTERFACE
EQU directives should appear near the beginning of a program, before their labels are used by
other program statements. If the assembler encounters a label before it has been defined, the
assembler has no choice but to assume the worse case, and assign the label a 16-bit address
value. This would cause the extended addressing mode to be used in places where the more
efficient direct addressing mode could have been used. In other cases, the indexed 16-bit offset
addressing mode may be used where a more efficient 8-bit or no offset indexed command could
have been used.
5.8.2 Form Constant Byte (FCB)
The arguments for this assembler directive are labels or numbers (separated by commas) that the
assembler can convert into a single byte of data. Each byte specified by the FCB directive
generates a byte of machine code in the object code file. Use FCB directives to define constants
in a program.
5.8.3 Form Double Byte (FDB)
The arguments for this assembler directive are labels or numbers (separated by commas) that the
assembler can convert into 16-bit data values. Each argument specified in an FDB directive
generates two bytes of machine code in the object code file.
5.8.4 Originate (ORG)
The originate directive sets the location counter for the assembler. The location counter keeps
track of the address where the next byte of machine code will be stored in memory.
As the assembler translates program statements into machine code commands and data, it
advances the location counter to point to the next available memory location.
Every program has at least one ORG directive, to establish the program’s starting place. Most
complete programs will also have a second ORG directive near the end of the program to set the
location counter to the address where the reset and interrupt vectors are located. You must always
specify the reset vector. It is good practice to also specify interrupt vectors, even if you do not
expect to use interrupts.
5.8.5 Reserve Memory Byte (RMB)
Use this assembler directive to set aside space in RAM for program variables. The RMB
directive does not generate any object code, but it normally generates an entry in the assembler’s
internal cross-reference table.
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M68ICS05KJOM/D