Abstract
The Assembly code we’ve been developing produces compact code compared to high-level languages due to not needing a runtime and each instruction only taking 32 bits. However, in the early days of the ARM processor, there were a lot of complaints that this was too large. People used ARMs in small embeddable devices with very limited RAM and needed more compact programs. Others created systems with a 16-bit memory bus that allowed 64K of memory—tiny by today’s standards and took two memory cycles to load each 32-bit instruction slowing down the processor.
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© 2019 Stephen Smith
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Smith, S. (2019). Thumb Code. In: Raspberry Pi Assembly Language Programming. Apress, Berkeley, CA. https://doi.org/10.1007/978-1-4842-5287-1_15
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DOI: https://doi.org/10.1007/978-1-4842-5287-1_15
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Publisher Name: Apress, Berkeley, CA
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Online ISBN: 978-1-4842-5287-1
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