RTC stop working with button cell

[Marzalan]

After checking the DS1307 datasheet, I found a note mentioning the chip malfunctioning when using a diode in series with the "Vbat" pin. I removed diodes D5 and D7 from the board, and put a Jump in place of D7, and now it's functioning normally.

If you remove ( short ) the diods, the cr1220 will suply voltage to mainboard, + main power will charge battery cr1220 all the time !