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SKP out of range

Posted: Mon Dec 27, 2010 12:45 am
by livingston
Ran into a new error today, SKP out of range. I guess the SKP operation can only skip 64 instructions?

First, why is that?

Second, is there any better solution to this than to just SKP to a label in the middle of the program, then SKP again to where we actually want to go?

Re: SKP out of range

Posted: Mon Dec 27, 2010 10:47 am
by frank
livingston wrote:Ran into a new error today, SKP out of range. I guess the SKP operation can only skip 64 instructions?

First, why is that?
Actually 63 is the max. If I recall correctly we figured people would probably not need to skip more than half the total length and the 6-bit count value worked better in the instruction decoder in the FV-1.
livingston wrote: Second, is there any better solution to this than to just SKP to a label in the middle of the program, then SKP again to where we actually want to go?
There may be but would need to see the code to offer any suggestion. You may be able to use the skip at the end of a program to add/not add in a result or not output to the DACs, etc.

Posted: Fri Dec 31, 2010 5:10 pm
by donstavely
Keep in mind that unlike a conventional processor, there is no advantage to skipping instructions in terms of processing time. You still only get 128 program steps, whether they are executed or not. So you can go ahead and do the processing, then just choose to use it or not. I think this is what Frank is getting at.