I want to use the RTC’s interrupt function ( minute timer interrupt) of my Maxi Automation. I find on the Maxi Automation pin-out datasheet that RTC INT is connected to port PJ7 ( AVR pin 79). But the PJ7 is a pure input/output ( not INTx or PCINTx). So how to catch the RTC interrupt ?
I also check on the AVR board and find one pad ( for soldering) named RTC/INT but it is not really connected to PJ7. Can I solder this pad to port PD3 ( controlino pin header INT0) in order to catch the RTC Interrup ? If yes which side of this pad is correct?
yes, you can use this pad marked RTC/INT. Pad close the the part of the text “RTC” (upper one when text is readable) is going to RTC output.
But there is also internal pull-up connected to +5V is on the board on the RTC output and with Internal pull down of the Interrupt input it will make divider so there will be maximum 2,8V on the processor pin. So it will be not proper LOG HIGH there, but shall work .
Hello.. I am trying to interface AT89c51 with DS 1307( a real time clock) which uses I2C Communication protocol. The problem is that Real Time Clock could’nt be triggered(started) after setting up the initial register values.I can read the same Data which i’ve sended to DS 1307 Registers again & again.