Mar 29, 2017 #1 M Mokthar Junior Member level 1 Joined Nov 26, 2016 Messages 18 Helped 0 Reputation 0 Reaction score 0 Trophy points 1 Activity points 157 Hi, Iam trying to isolate uart communication between Metering mcu and RF mcu. I tried with 2 different way. one i used Analog Digitals Digital Isolator. There is no issue while communicating with that. Then the other using Optocoupler PC817 it works for first few cycles and there is no communication after that. How to fine tune the opto circuit. Schematic attached here for reference. With Regards, Mokthar
Hi, Iam trying to isolate uart communication between Metering mcu and RF mcu. I tried with 2 different way. one i used Analog Digitals Digital Isolator. There is no issue while communicating with that. Then the other using Optocoupler PC817 it works for first few cycles and there is no communication after that. How to fine tune the opto circuit. Schematic attached here for reference. With Regards, Mokthar
Mar 29, 2017 #2 andre_luis Super Moderator Staff member Joined Nov 7, 2006 Messages 9,601 Helped 1,190 Reputation 2,399 Reaction score 1,208 Trophy points 1,403 Location Brazil Activity points 55,714 You did not mention the kind of I/O of each device: Pushpull? Open-collector? with or w/o pullup? any circuitry connected at these nets? etc...
You did not mention the kind of I/O of each device: Pushpull? Open-collector? with or w/o pullup? any circuitry connected at these nets? etc...
Mar 29, 2017 #3 M Mokthar Junior Member level 1 Joined Nov 26, 2016 Messages 18 Helped 0 Reputation 0 Reaction score 0 Trophy points 1 Activity points 157 Hi Andre, The circuitry connected with it is attached here. There are 2 circuits one with digital isolator which works fine. Other is with opto where i have problem in communication. On both sides i have connected with Tx and Rx pins. With Regards, Mokthar
Hi Andre, The circuitry connected with it is attached here. There are 2 circuits one with digital isolator which works fine. Other is with opto where i have problem in communication. On both sides i have connected with Tx and Rx pins. With Regards, Mokthar
Mar 29, 2017 #4 Easyrider83 Advanced Member level 5 Joined Oct 11, 2011 Messages 1,608 Helped 374 Reputation 748 Reaction score 363 Trophy points 1,363 Location Tallinn, Estonia Activity points 8,575 PC817 is a low freqency device. Maximum freqency is 80kHz. So, 9600 bps should work, more is a question.
PC817 is a low freqency device. Maximum freqency is 80kHz. So, 9600 bps should work, more is a question.
Mar 29, 2017 #5 M Mokthar Junior Member level 1 Joined Nov 26, 2016 Messages 18 Helped 0 Reputation 0 Reaction score 0 Trophy points 1 Activity points 157 Easyrider83 said: PC817 is a low freqency device. Maximum freqency is 80kHz. So, 9600 bps should work, more is a question. Click to expand... Here the baud rate is 4800 bps. is there i need to work out on my resistor values? If so where did i made a mistake? With Regards, Mokthar
Easyrider83 said: PC817 is a low freqency device. Maximum freqency is 80kHz. So, 9600 bps should work, more is a question. Click to expand... Here the baud rate is 4800 bps. is there i need to work out on my resistor values? If so where did i made a mistake? With Regards, Mokthar