Page 155 - Introduction to Microcontrollers Architecture, Programming, and Interfacing of The Motorola 68HC12

] 32 Chapter 5 Advanced Assemblers, Linkers, and Down loaders

Figure 5.9. Flowchart for Example Control Sequence

Finally, one should consider attaching a flowchart with each subroutine as part of the
documentation. Flowcharts are particularly useful for detailing complex control
sequences. For example, the rather impenetrable sequence in Figure 5.8 becomes more
fathomable when displayed as part of the subroutine flowchart shown in Figure 5,9.

5.6 Summary

In this chapter, we learned that a more powerful assembler can help you write much
larger programs than you would be able to write by hand coding in machine code or by
using a simplified assembler. Relocation, conditional assembly, and macro expansion
permit the programmer to significantly expand his or her techniques. However, high-
level languages provide alternative means to these and other ends, so that high-level
language programming has superceded the more powerful assembly-language
mechanisms described in this chapter.

Do You Know These Terms?

See the End of Chapter 1 for Instructions.

cross-assembler servers relocatable linking loader
host computer print server section conditional
target machine workstation linker assembler
downloader records parameter file macro assembler
monitor program checksum memory macro
bootstrap S-records segment library
local area network absolute loader absolute section