Byte Me - PLC5

I have a status word being read from a device (N address). Bits 00 to 07 have a BCD error code number, and bits 08 to 15 contain a BCD error location code number. I need to split this word and convert the BCD values to decimal, so I can use the separated values in compare instructions...to turn on various fault bits to display error information on a PanelView. What's the easiest way to get these byte values separated...and then converted to decimal. Thanks in advance!!

Give this a try, it is untested and has no warranty.

Hey...thanks Ken!! That will work. Never knew about that "divide by 256" thing...even after all these years.

bluenoser,

I like the /256 method.

You can also use the BTD (Bit Field Distributor) instruction to move the top 8 bits of the source into the lower 8 bits of a destination word. Of course you still have to convert to integer.

I've used the BTD where space was at a premium (IO to/from a 1394 servo). For 1394 to PLC5, I pack what I can into the 99 bits in the 1394's RIO data table then disassemble the integer into it's separate parts with the BTD instruction. For PLC5 to 1394 I assemble the 99 bit output table with the BTD then use GML to take it back apart.