+ 4. Design a mod-12 left-shift Johnson counter with counting sequence: OOO OOO OOOOO ooool, OTOTOOLI, OD1||||, QUI, TTI, NO, NOTO, TOTOO, LUOTO00, LOTO OTOJO, and then back to Ojoojooo by using two 74194 4-bit bidirectional SRGS (see Fig. 2(a)) and inverter (if necessary). Note: you should clearly mark the connections of So, S., and SL SER. (12%)