So adding a Linkit connect module and add a low cost RTC (both DS1307 or PCF8563),and a SD slot and some buttons, the next main board almost finish,(Still need a buzzer and a photocell) hope i can finish coding before Arduino Day event in Taiwan.

and by the way, the IV-18 board still have to make another version, because that SSOP version of MAX6921 is VERY EXPENSIVE and HARD TO BUY, so I'll try to build a version made of HV5812 and LM9022(equals to LM4871 by the way)