non-volatile memory and IB-201

[8bits]

Hello All,
I am trying to use IB-201 (MOVED) to write to non-volatile memory at V7400 and them have the  RAM V7400
overwritten at PLC restart from the non-volatile V7400.
I have also sent a tech support request here as well.

The manual indicates that to write to non-volatile memory the MOV instruction is the only way to do that. Also, it is my understanding that on a PLC restart, the non-volatile memory locations (V7400-V7577) are automatically written to the companion RAM locations (V7400-V7577).

I also understand that the only way to read the contents of non-volatile memory is through a restart. In other words, there is NO way to access the non-volatile memory from the ladder program itself.
It seems to me that the IB-201 may not actually write to the non-volatile location and perhaps I will have to use the MOV instruction instead of the IB-201 .

Looking forward to some additional insight on this. I think I will try the MOV method and just specify the number of word to move is 2 (K2) and then see if it restores on restart.

Thanks.

[franji1]

All MOVE does is a macro for the actual instructions:
LD parameter1
OUT parameter2

and MOVED

LDD parameter1
OUTD parameter2

So these will not write to the ROM based values.  So you need to use the MOV instruction to write to the ROM-based memory

[8bits]

I figured it out and is as you indicated. I changed the logic and used a

INCB          ;start of the rung
LD K2         ;number locations to move
LDA O2500  ;the source data
MOV V7400 ;writes to non-volatile memory

It is a little confusing on using the IB-201 and it makes one think that it is a special MOV