The ARM9TDMI is a member of the ARM family of general-purpose microprocessors.

The ARM9TDMI is targetedat embedded control applications where high performance, low die size and low power are all important. The ARM9TDMI supports both the 32-bit ARM and 16-bit Thumb instruction sets, allowing the user to trade off between high performance and high code density. The ARM9TDMI supports the ARM debug architecture and includes logic to assist in both hardware and software debug.

The ARM9TDMI supports both bidirectional and unidirectional connection to external memory systems. The ARM9TDMI also includes support for coprocessors.