过这两天阅读ARM926EJ-S技术参考手册，我已经明白这里的指令/数据SRAM的用途了，实际上这两个SRAM是连接在ARM核中一个称为紧密耦合存储器（ Tightly-Coupled Memory (TCM) ）。这个东西有点复杂，网上关于这个编程的资料也很少，具体怎么用，大家看手册了呵。以下是一部分摘录，具体参见ARM Technical Reference Manual
The ARM926EJ-S processor enables low latency access to external memories using the
Tightly Coupled Memory (TCM) interface. The term tightly coupled memory refers to
the relationship between the ARM9EJ-S CPU core, and the operation of the memories,
where there is a strong correlation between the instruction and data access activity of
the ARM9EJ-S and the accesses made to external memory. This is in contrast to the
accesses made to the AHB interfaces, that are relatively decoupled from the ARM9EJ-S
core.
TCMs are intended for storing certain types of critical code or data, where low latency,
deterministic access is required. TCMs are not necessarily the best choice for all types
of such code or data, if code or data exhibit a high degree of spatial or temporal locality
better performance can be obtained by using cache memory.
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