 | | H8 & unaligned word accesses
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I discovered an interesting "feature" of the H8 series processors used in the RCX. It will only affect people using raw H8 code on the RCX, such as those of us using LegOS, and perhaps pbforth. The H8 does not support unaligned word accesses. If you (...) (25 years ago, 11-May-99, to lugnet.robotics)
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| | RE: H8 & unaligned word accesses
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(...) Right you are Matt. This created a bit of trouble when I was porting the original pbFORTH code over to the H8. I THINK this is because the H8 core is extensible to a full 16 bit machine - or even 32. The "8" in H8 is a misnomer except at the (...) (25 years ago, 11-May-99, to lugnet.robotics)
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| | RE: H8 & unaligned word accesses
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(...) I am currently using the H8S/2144 processor at work. The above statement is totally correct - the H8 series is directly compatible with the 16-bit H8S series. Because the H8S is a true 16 bit processor, internal memory is always accessed as a (...) (25 years ago, 11-May-99, to lugnet.robotics)
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| | RE: H8 & unaligned word accesses
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(...) Brian, how does the rest of the Hitachi H8 line stack up? Up until now, I have been using Motorola exclusively, except for the odd PIC design and even a 4 bit NEC 75000 series design!!! The Hitachi gnu chain seems pretty decent, even the (...) (25 years ago, 11-May-99, to lugnet.robotics)
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