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General Category => Do-more CPUs and Do-more Designer Software => Topic started by: PLCwannabe on December 30, 2020, 10:58:08 AM

Title: Indirect addressing
Post by: PLCwannabe on December 30, 2020, 10:58:08 AM

Is there some way to use indirect addressing in a For Loop for memory locations that are offset by more than 63? Eg.
v100*v1100    (repeat 50 times) V0 is the index loop.

v[v0]*v[1100+vo]   This doesn't work.

Title: Re: Indirect addressing
Post by: BobO on December 30, 2020, 11:52:20 AM

Quote from: PLCwannabe on December 30, 2020, 10:58:08 AM

Is there some way to use indirect addressing in a For Loop for memory locations that are offset by more than 63? Eg.
v100*v1100    (repeat 50 times) V0 is the index loop.

v[v0]*v[1100+vo]   This doesn't work.

Simple displacements are limited to 63, but you can use full expressions as array indices in a MATH box.

Title: Re: Indirect addressing
Post by: PLCwannabe on December 30, 2020, 02:39:12 PM

Well, that was really easy! Thanks.

Title: Re: Indirect addressing
Post by: BobO on December 30, 2020, 02:47:50 PM

Quote from: PLCwannabe on December 30, 2020, 02:39:12 PM

Well, that was really easy! Thanks.

It's a little confusing at times...why certain limitations some places and not others. in the MATH, we have the full power of the math stack and expression language, but in individual parameters of other instructions, we are limited by what can be packed into a single parameter.

Another thing people frequently miss is that the MATH box *output* can also be a complex array expression.