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Comment by dmitrygr | Hacker News Reader

@author:

   1     @ Set BR8 field in GPIOA_BSRR, to clear GPIOA8
   2     movw r1, #0x0000
   3     movt r1, #0x0100

you can just use a mov to get that value. Any 8-bit value shifted left any number of bits is synthesizable using one MOV

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This is true! If I was writing something to be optimal speed- and size-wise, I'd do that. I think I just liked the consistency with the other parts of the code where using both was necessary :)

Oh actually I was being sleepy and hadn't understood what you'd said! I hadn't realised you could do that actually, neat, thanks!

So you could do `mov r1, #0x01000000` right? nice.

yup, some other constants are also loadable in one instr, of the form 0xXX00XX00, 0x00XX00XX, 0xXXXXXXXX where XX is any byte

Do you not need the usual LSL, or does the assembler take care of that?

it does, yes

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