BTW revision:2 also said much. For real commercial chip it is fortune to see revision 5, but usual for market something more than 10. This is because chip manu

BTW revision:2 also said much. For real commercial chip it is fortune to see revision 5, but usual for market something more than 10. This is because chip manufacture is iterative process, you spent at least 3 revisions to achieve predictable yield percentage, and then each revision will make yield percentage better and better economy.