first version 022001 has 128K flash, 16K ram, newer version 022005 has 256K flash, and 32K ram, otherwise it appears to be the same part, of course it cost more, because of the extra memory
Caution.. The foot-print is different too. There is an extra pin added to the 222005-00 that is not available on the 022001-00. They added the VREF input reference voltage at pin 6.
Physically...this only added a single pad to the footprint and all the other signals remained in the same location.
Which would make the two parts compatible if you aren't using the VREF signal. HOWEVER.. CAUTION HERE.. Relative to the schematic symbol... The pin numbers starting at pin 6 are all different incremented by 1) !!
A side note.. be very careful when you look at foot print layouts in the documentation. Sometimes they use the BOTTOM view and sometimes they used the TOP VIEW.. very confusing at first.