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As I understand the STM32F4 programming manual (DM00046982), or the Cortex M4 TechRefManual, a Cortex M4 processor as the STM32F4 can only work with Thumb mode (T2 I think).
But if I use the ST4Discovery (with STM32F407) with Keil uVision, in the Dissambly I see as well 32bit-ARMv7 code (32 bit commands), as Thumb code (16 bit commands). E. g. for LDR commands it seems to use the Thumb command for small offsets, and the 32-bit ARM command for larger offsets.
This really puzzles me very much - how can I see 32bit-ARMv7 in the dissassembly listing, if the processor can only understand Thumb code?
Thank you for the fast answer.
Is "ARMv7" a subset of Thumb-2, or is this exactly Thumb-2?
If I look at the LDR command in the ARMv7 TechRefManual, there are 4 encodings named: - "Encoding T1, All versions of the Thumb instruction set", - "Encoding T2, All versions of the Thumb instruction set", - "Encoding T3, ARMv7", - "Encoding T4, ARMv7"
Can CortexM4 / STM32F4 use all of these 4 encodings? (I assume Thumb-2 has nothing to do with "Encoding T2"?).
... sorry for the questioning, I think I got it now:
ARMv7-M = Thumb-2, and T1-T4 has nothing to do with Thumb-2 (In my last Email I forgot the "-M" at the ecoding types T3 and T4 for LDR). Thank you.