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Patterns in Register Map Design

posted by janrinok on Monday May 22, @05:31PM   Printer-friendly

owl writes:

https://www.devever.net/~hl/regmap

If you've ever had to write a program which interfaces directly with hardware — perhaps while writing a program for an MCU or embedded system or a kernel driver — you may have noticed a few common patterns in register map behaviour and design. I'm not sure anyone has ever really collected them together, so I decided to make a list of all the ones I can think of.

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  • (Score: 3, Informative) by owl on Tuesday May 23, @02:17AM

    by owl (15206) Subscriber Badge on Tuesday May 23, @02:17AM (#1307527)

    Now that you mention it, I think the Alpha's "nop" instruction was actually something like

    add r0,r0,r0

    (assuming r0 was the "always zero" register), that would add zero to zero and store the answer in the register that was always zero. The result, a "NOP" instruction, without having to explicitly have an actual "NOP" instruction built into the hardware.

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