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General Category => Do-more CPUs and Do-more Designer Software => Topic started by: Bolt on August 20, 2019, 07:22:59 PM

Title: Using Indexed Variables in a SWAPB Instruction
Post by: Bolt on August 20, 2019, 07:22:59 PM

I think this is a minor glitch in DmD, I can't use sequential or close indexes in this scenario.  See attached example.  Changing the destination to V318 for example works fine.  It'd be nice if you could fix this?

Title: Re: Using Indexed Variables in a SWAPB Instruction
Post by: brucek on August 21, 2019, 06:53:39 AM

looks like in the instruction you have 4 elements selected and it should be 2. N is a word I think.

Title: Re: Using Indexed Variables in a SWAPB Instruction
Post by: franji1 on August 21, 2019, 09:47:13 AM

Quote from: Bolt on August 20, 2019, 07:22:59 PM

I think this is a minor glitch in DmD, I can't use sequential or close indexes in this scenario.  See attached example.  Changing the destination to V318 for example works fine.  It'd be nice if you could fix this?

Good catch.  Fixed.

Basically, if both elements are arrays to the same block (e.g. N), then the PLC logic is responsible to ensure that the two array index/element count ranges do NOT overlap.  (If they are identical, e.g. Source and Dest are both N[V42], then it will flag THAT as "overlapped" since they are the same array index to the same block.)

Caveat Emptor.

Title: Re: Using Indexed Variables in a SWAPB Instruction
Post by: franji1 on March 25, 2020, 10:08:52 AM

Fixed in Designer 2.7.  The range validation was incorrectly interpreting the V array index as a normal block index.