Hi guys. i have a simple atmega16/32 project with three relays (i need two of them to be switched on at the same time). when the internal code changed to put only one bit output at portd every thing run fine. but when i try to control two relays and send two on bits at the port the mcu reset. firstly i thought it might be power being low when the two relays switched on but i remove the relays and the problem persist. the portd drives bc109 transistors each have a base resistor of 1k which limit the output current at the same level of the mcu.

please help me because i have only few days to finish the project

 

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