antoniasse wrote:

> I=B4m looking for retlw instead tblrd (table-read instructions)
> becouse I have some codes writes for the 16Fxxx and I have
> to change for the 18Fxxx series, Then In this case,
> it will be easier for me.

Luis,

If you're porting table lookup code from the 16F series to the 18F =

series then don't forget that the index value added to the program =

counter must be multiplied by 2 on the 18F.

I usually write my table code something like so:

    MOVLW HIGH (table_start)
    MOVWF PCLATH
    MOVF  index,W
    ADDLW LOW (table_start)
    SKPNC
     INCF PCLATH,F
    MOVWF PCL

For the 18F series I'd change it slightly to:

    CLRF  PCLATU
    MOVLW HIGH (table_start)
    MOVWF PCLATH
    RLNCF index,W
    ADDLW LOW (table_start)
    SKPNC
     INCF PCLATH,F
    MOVWF PCL

I also usually make sure the index is in range for the table. This can =

be done with a single ANDLW instruction as long as the length of your =

table is an even power of 2. You may wish to write a macro that does =

everything for you and then your 16F code can 18F code can be made to =

look identical.

Scott
-- =

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